Talk to Gynecologist on Pregnancy Issues

mam i getting a issues in my periods they be like irregular from last three months from last 3rd month my date was 30 then it move to 4 and the 10 mean i was getting my periods on the last date of my last periods but this month i didn't get my periods i was expecting on 10 but i got spotting on 14 i had done pregnancy test but it was negative i am worried please suggest me what should i do