Discharge stops after unprotected sex

I am used to vaginal discharge every day that's what it's been like ever since I've started my period but I had unprotected sex yesterday (w/o a condom, he did not cum but not sure about precum)  I've got no discharge today I'm absolutely dry and a weird pressure in my stomach... Is this normal? I am on birth control but have to take acne pills as well as topicals which make it less efficient. I have also began to have an allergic reaction to condoms which is why we didn't use them. I don't want to be pregnant. ?