No signs of pregnancy. Missed periods?

Hi! Me and my husband trying to get pregnant for the last 3 4 months now, last month I had my periods on 6th N My cycle is 28 or 29. I track my fertile window and plan things accordingly. This month it was due on 3rd but i am late by 8 days that's the first time ever my periods got delayed. I read a lot about early signs of pregnancy but sadly i don't feel any symptoms apart from mild cramps in lower abdomen like the ones during chums. I am so confused and haven't taken any pregnancy test. Just tried homemade diy pregnancy test with negative result. I read that after a week late periods one can get accurate result as hcg increases in urine n stuff. I am worried sick I m losing patience now. Am i pregnant or it is just some other health issues related to late or missed periods? Please help me Thank you