My dog is throwing up :-(

Eating grass = they don't feel well is a myth.  Yes, they may eat grass when they aren't feeling well, but they may eat grass even if they are feeling fine.  So I wouldn't worry about that.

How often is he vomiting?  Noticing blanket is worrisome, he could have an obstruction.  But usually that's accompanied by lethargy and not eating.

Are his stools firm?  Did you recently change food? 
 

VET for sure.  Two days is too long.  How long since he's had a bowel movement?  If he's prone to eating 'stuff' he could be obstructed (which will cause anything he has eaten since to back up to the stomach and it causes them to be nauseus).  Eventually the bowel empties (beyond the obstruction) but this can be life-threatening -- vet ... now (particularly given what you've said).

His stools are a bit loose. He eats canidae lamb and rice, but they recently changed their formula and that's when his stools have loosened. (that's kind of gross...lol) before the formula change his stools were firm. 

His last bowel movement was this morning, but again it was loose. It's not a constant throwing up. It just every now and then.
 

 Keep a close eye on him. If he doesn't go poop tonight or if it is more loose than this morning then you'll probably want to get him checked out. Vomiting, loose or no stool and acting like he has abdomen pain (stiff walk, slow to move around) etc. are signs of an obstruction.

What do you constitute as "now and then" once a day?  Once every hour?  

If it's very regularly call a vet.  That's not normal.  But, if it's after he eats with loose stool, has an apetite and is playing, I'd put him on a bland diet after fasting him for 12 hours.  Bland diet boiled chicken and white rice (for a few days).  And change his food, mixing in the kibble to the bland diet slowly.  The new formula is probably not agreeing with him.  Look into a higher protein food, orijen, innova, evo, etc.

If that doesn't clear up the vomiting and loose stool vet time.

But if he starts showing ANY signs of lethargy and loss of appetite it's EMERGENCY vet time.
 

Ya that's what I will do. If he continues to throw up I'm going to take him to the vet to get him checked out.

How big is he, weight wise?  And how old?

I'm not entirely sure, you may have to guess.  I'd probably consider 3/4 cup cooked rice and entire chicken breast per meal... maybe more or less, you'll have to decide when you see how much that equals and how he does on it.
 

I homecook for my dogs ... for a 50-60 pound dog probably 1 cup total cooked food (packed in the cup).  Keep the rice VERY cooked -- keep a lot of water in it and cook it until it is split and blown out - you can put the chicken in there to cook it in the rice - and I wouldn't use chicken breast - use dark meat if you can (it's got more minerals and stuff in it - increases the nutrition without increasing risk).  *don't* use brown rice -- it's hard to digest ANY time. 

You might want to add just a BIT of canned pumpkin -- maybe a tablespoon per meal (don't buy pie filling, just canned "solid pack" pumpkin -- will keep easy in the fridge in an airtight container).  It's one of those things that will add fiber -- too much will make diarreha, a bit will firm things up. 

Since the dog is holding SOME food down that's fine to try cooked food.  But if the dog *stops* pooping at any time -- vet ... fast. 

However, I'll interject here -- the higher protein kibbles don't agree with all dogs.  I home cook, but I don't give much grain at all (hardly any in fact).  But I don't do a high protein diet (most of my dogs are seniors) and I add cooked veggies.  LOTS of them.  A wide variety of them -- it adds nutrition, bulk and is satisfying.  Just a thot for you.

Does your dog heave from the stomach or does it just suddenly lose a lot of food from it's mouth? There is a difference between regurgitating and vomiting. It's important to know the difference. My dog did both, actually. She would go for a few weeks okay then have a full week or two of vomiting and regurgitating. I wasn't aware that the regurgitation was becoming a bigger problem than vomiting until this past week. When she finally got tested after two years of other kinds of tests for vomiting issues, she was diagnosed with megaesophagus. It's growing more and more common in dogs. If your dog has a deep-chest like (examples ;) Great Dane or a German Shepherd or a Boxer, it is likely more inclined toward digestive issues anyway, particularly bloat. But these same dogs are, along with other breeds, can be inclined to having acid reflux problems or other digestive problems and the megaesophagus. That is, simply put, an esophagus that has become stretched out (mega=big, esophagus meaning what it  - the tube leading from mouth to stomach). A stretched esophagus allows the food a dog eats to drop down below the line it should be traveling in order to get into the stomach. The stomach opening will be up high (toward the spine) while the food will be more toward the belly of the dog with no way to get up to the stomach opening. I'm talking about an esophagus being a small tube (guessing at this: about an inch or so in diameter) that becomes the size of your upper forearm. On top of being stretched out, it may not be have motility - the ability to make the wavelike motions necessary to move the food toward the stomach. There can be other conditions related to this too.

 IF your dog is regurgitating instead of vomiting, you need to know what's causing it. Of course, if it's vomiting, you need to know about that too. Either way, it's obvious that you should talk with a vet about this. There are many things it could be either way.