Screaming and crying at the vet.

Sounds to me like she's gotten a tad manipulative -- if you coo and "ohh it's ok bay beeeee" her she may decide she likes the attention.  But that being said, it only takes one bad experience to turn on terror.
 
Being proactive works wonders -- don't wait for the next 'vet appointment' to take her back to the vet.  Pack 3 small baggies of treats -- something she likes even if you have to break them up in small pieces -- or slice hot dogs super thin -- whatever is acceptable to you to give as treats -- even Cheerios can work for this). 
 
Go TO the vet, on leash, the whole drill -- but call THEM ahead of time and warn them you are coming and find out a good time when it's not too busy.  This is JUST for training.
 
Walk in and hand the receptionist all 3 bags of treats.  Tell her one is for her, then one is for the techs and one is for the vet and if they had just a minute could they see her and just 'make friends' for a minute and try to erase the trauma of the last time.
 
Don't take up much time, but letting each of those groups make friends with your dog.  AND then the next time, DO take a baggie of treats and just let the vet know it is his to give either piecemeal as he has to do things or afterward but that you are trying to mitigate the damage that last horrible time may have done ...
 
My dogs NOW think the vet is the best place on the planet.  I don't always take treats, but I DO if I know we're headed for blood draws, or anything that may 'hurt' or be traumatic.  The vet honestly appreciates SO MUCH my efforts to keep him being the 'good guy'.  It works.  Truly does.
 
But let the bag be an "he can have ALL of that" thing -- don't make them 'stop' -- there's something mentally FUN about being able to give it ALL to the dog.  And if you make the effort to help your vet and staff be your dog's bestest buddy -- it will reap benefits for years.

Thank you for the adivce!  I will do that...but the dog is fine until they start "poking" at her with needles and things.  She lets them check her teeth and all of that without much trouble. 
 
I'm wondering if something happened at the kennel she used to love visiting and now hates.

If your dog doesn't offer to bite, then you may be able to give a treat at the moment of vaccination.  That way maybe she will associate needles with treats, at the minimum she'll be distracted with the treat.

They tried the treat thing...she ignored it because they had things in their hands.  This is also a problem with her for nail trimming...she knows you're up to something and evades you.  I'm afraid we might have to "calm her down" a little before going.  I'll take her up there next week to weigh her (she was a few pounds overweight last time from eating cat food we didn't know about) and see how she does. 
 
 

I think I made the point -- you gotta make these treats worthwhile and usually vet treats just aren't 'good' enough.
 
A bit of valerian root tincture or some Hylands Calms usually will help with something like this if you want to give it before you leave home. 
 
But take her in when you do NOT have to have work done at the vets -- set her up to win, not fail with this.  Let her have a time or two there when it's not scarey. 
 
And you might want to try using a Dremel on her at home, rather than taking her for nail clipping.  It's less stressful -- another thing that requires training but it's worth it.