I need some advice!

So, i lost my v card some months ago with my bf, we used a condom and it was really good, my period came last two months but its alredy a month late now (it came the two months after that, im mising the third one) and im really paranoid now, i've been through A LOT of stress lately aand even though i know i should be safe, i'm scared about what could be going on, i dont have a regular period either :/ Any advice or idea about what could be going on?