Pain :(

At the very beginning of this month, 2 days after my period ended, my boyfriend and I had sex and he came in me, 2 or 3 times in 2 days. Since then we have been using condoms as we both decided to wait a little longer to properly ttc. I've been totally fine, but yesterday I got up to go to the bathroom and on standing up or moving my stomach (on coughing ect) I get sharp standby pains really low down in my stomach, it's especially bad when I sneeze! And today I had a very light show of blood for 2 wipes and its stopped, periods due tomorrow but I'm irregular and have had none of the usual signs, cervix is high(super high) I think it's closed and decently firm.
Any ideas what this could be?