in need of advice

Danielle
Hey girls im 18 and have had my periods since the last time i had intercourse which was may 13th every singlemonth meaning june july and august i have had had my periods, i took a home pregnancy test and it came back negative as well as blood test and came back negative, which if i was to be pregnant i would be 4 months by now??? my friends kind of scared me telling me that i could still be pregnant??? Is that true should i still be worried? Can blood test at this point be wrong my boobs hurt but i think thats because i been squeezing them everyday for a week now! Just to check is theyre sore.. i know ridiculous right? But everyones telling me that u can still have ur period and be pregnant and all this YouTube videos about women who didnt know they were pregnant! Are really freaking me out
Anwyays it would be really helpful if u guys could answer my questions thanks god bless