3rd YEAST INFECTION IN 2 WEEKS?? HELP! WORRIED!

Okay so here’s the whole run down.

I am sexually actively with my boyfriend (who was a virgin before me) and i was also a virgin. we just started having sex without condoms because I am one the pill (but we pull out as well). I just got out on a different pill this cycle bye. Two weeks ago, my vagina started to itch, pretty badly. Then I got white clumpy discharge. I’ve never had a yeast infection before but it lined up with the symptoms on the internet. So that day, I bought Monistat 3. I used it and I had symptom relief until I accidentally used a tampon because i started my period. I was unaware i should not do that, and the itching came back. so, assuming the yeast infection came back, i bought monistat 1. same thing, symptom relief for three days then, my boyfriend and i thought it was okay to have sex. well he penetrated me and it hurt so badly. it lasted 30 seconds before i started crying. the next day, the itching came back, which is today. Now, I have bought another round of Monistat 1 and debating if i should use it now or wait. the itching has spread from my vagina to anus as well (which according to the internet is normal), back pain (might be from stress), but no sores or inflammation, just this itch. Do you think I have something else? Should i use the new monistat 1 or wait to see if it clears up? PLEASE I NEED HELP ASAP