my girl came in heat about 12 days ago and it was typical....then she had next to no blood and my stud wanted her and was howling for 2 days and she was flagging and now she is dripping blood again very heavy and stud dog has little to no interest.

I wiped her and there is no bad smell just lots of bright red blood again...is this normal?

She could be having a split heat. Otherwise sounds pretty normal. Sometimes the stud dog gets all excited about the bitch a week or two before she's really in heat. Get progesterone testing, and if she's ready and they don't want to tie, do an AI.