I need advice!!

My boyfriend and i were both virgins and we had sex for the first time yesterday. He wore a condom, but I’m not on the pill because of some unresolved health issues. (Basically I’m 15 and just got my first period last month, but my next one is supposed to start tomorrow) my boyfriend came in me with the condom on and then kept going to try to get me to orgasm. Afterwards when he took the condom off it kinda spilled all over the place and he said it was cuz he hadn’t came in awhile so “it was a big load, I kinda overfilled the condom a little haha.” However, I’ve lost a bit of weight and periods can be irregular at the start so I’m worried that what if some of his cum got in me when he “overfilled it” and kept going and i wont know if I’m pregnant or not because of my irregular periods😬😬 what do I do??