4 days late ... what could it mean?

Hi ladies, wanted to ask for some advice. I’m 4 days late and have cramped off and on all 4 days, it hasn’t been intense cramps just bothersome and they don’t last very long through the day. I have had no spotting either. I took a pregnancy test on day 2 but it came out negative, I’ve read I should really wait until day 5 or after because my HCG levels might not be high enough yet. I wanted to see if any other women have gone through this and what the outcome was. I don’t want to get too excited, like most, we have been trying to conceive for years now. Thank you!