Possible pregnancy? **please reply!!**

My boyfriend basically came on my ass a little, but most of it went onto himself. I’m pretty positive none of it got in my vagina but it was mostly on my ass/lower thigh. He sometimes rubs his dick against my ass and sometimes tries going into my ass (anal) without condoms. He’s never been directly inside my vagina. He once accidentally pushed and it went in my vagina by less than an inch but he definitely didn’t cum. And I’ve never noticed any precum or anything with him so I don’t know what to expect. My period is late by 11 days but I also just switched to a new birth control pill with a different dosage. I’m pretty sure I get discharge before my periods and right now I’m getting a bit of discharge, but I read online that early signs of pregnancy is getting discharge when you’re supposed to be on your period, frequent urination, etc. I’ve noticed that I’ve been peeing a little more frequently but I think it’s because I’ve been doing a lot of exercise and drinking a ton of water. Anyways, could i be pregnant? Is there any chance? I’m on birth control and he’s never came inside me or anything, the only stuff that happened that I’m worried about is what i mentioned earlier. Please help.