This happened during my periods and now im a little tensed about it. Im not very clear on how the chances work in such a situation. Bit awkward to ask anyone i know so asking here, pls dont judge.
The chance is low but not fully zero, since cycles can be irregular and sperm can survive a few days. If you are worried about pregnancy, a test after your next expected period or a chat with a gynac will give clarity. Better to know for sure.
Dont spiral over this yaar. Risk on actual period days is low. If your next period is late, take a home test and stop the guessing, thats the clearest way.
I used to worry about exactly this stuff before I planned my pregnancy. From what I understood the timing makes it unlikely but not impossible. A test clears the doubt fastest.
Generally the chance during periods is quite low, but no one can promise zero. If you really want to be safe use proper protection going forward. And if a period is missed, just do a test.