Why does my dog acting weird, vomiting, shaking and licking?

Hi, my dog has been acting wired these days, she is 2 years old and she was a really happy dog. But recently she doesn't play, she doesn't run and she get mad so fast. But thats not only part make me worried, she ask for caress and everytime is touch her she move her butt in sudden (it's like something bothering her). And sometimes she is shaking when i touch her. These days she only can be find near the house door. She was on heat last week, but the bleeding has been stop for 4 days, i use pampers when she was on heat, and since she is not using pampers any more (4days) she been licking her private part alot (maybe every hour). So i took her to the Vet (2days ago) but they said it's a skin problem around her private part do they gave me a cream to apply. In same day they did her vaccinations also. The day after (yesterday) she vomited brown 3 times in row and i took her to Vet again, but after check they said she is normal and no fever. So they gave some pills for her vomiting be stop.