Wonky periods, four negative pregnancy tests results

I am 18 years old, I do have bad anxiety in general. I had sex in February between the 19th-23rd. I was on my period but it stopped and we ended up doing Things. Within minutes my period came back and we stopped. He didn’t finish in me and I’ve been scared since that I’ve been pregnant. I waited for my March period to come and it did, it was light and spotting ( combo of both) the first day I took a test and it came back negative. Still scared I waited until April and my period came again, but mostly spotting one day of lightness. I took another test and it was negative. I think my anxiety has been causing false symptoms because this is always on my mind. Scared to be pregnant, scared to tell my parents what’s going on. I took a test yesterday and that was in fact negative as well. The “symptoms” I’ve been having is just a weird feeling in my stomach, nausea and as of today my nipples started hurting. I haven’t had sex since February. Can someone please help me? Today I’ve felt some stinging in my stomach and my four results were negative