Irregular period or Pregnant? (Sorry for the long summary)

Hello, Im a 18yr old sexually active college student. My boyfriend and I had protected sex a little bit over a month ago. Because I was paranoid, I did check the condom afterwards and there were no tears or holes. I was due to get my period a week afterwards but I missed it. I do get irregular periods but I havent skipped a month since I first started getting my period. Currently, I have skipped 1 period and am due to get another period today according to this app but i javent gotten my period. I did take two clearblue pregnancy test on different dates (1 a week after my missed period and the other this past week) and both came out negative. I dont really feel different or notice any pregnancy symptoms and my weight changes sometimes I gain and lose weight relatively fast. I am also dealing with a family death so im aware I am a bit stressed. I think im just asking for some advice on what to do now? and what BC would be recommended... Thank you all, From a stressed out college student😊