Late period, negative pregnancy tests

Hello everyone! I feel like i am going crazy over here. To start off, my periods are usually light with the first day hitting hard maybe around 4days? So, if im going by when my periods are which typically seem to happen last week or so of the month, my last reported period was end of July that I for sure know of. Looking at dates and all, I believe that I 100% did not have a period in August at all. My fiance and I typically have that time once or twice a week so in August I know we did it. But my period would be im guessing 14-16days late by now? Ive been having alot of symptoms, but negative pregnancy tests. Ive been having alot of cramping in my fupa area & lower back. Has been cramping for about a week, almost loke period cramps. Ive been extremely tired than normal, I've also been feeling i guess you could say "tired dizziness" im usually also up early in the mornings about 6-7am and never take naps however I've been seeming to sleep in until 11am-12pm ish and taking naps. Ive also taken UTI tests and those have been negative. Has anyone ever gone through this? Had late positive tests? Could there be a chance im pregnant? Thank you all for reading!! I have definitely been feeling weird or almost like out of the loop lol.