TMI- What can this be?

So I started getting these small bumps near my vagina & on my ass. They don’t burn and they don’t itch. I had sex a week ago and again yesterday. Has anyone ever had this problem? Or something similar to it?

(Side note: My boyfriend and I have been together for 5 years).

Update:

- Recently started taking birth control

- Shaved last week

- Time of the month ended 4 days ago

- Had unprotected sex