Those cramps happen when you are pregnant too, just like period cramps! very normal in pregnancy. Many women get a lot of their period symtoms and find out they are pregnant. I had cramps a lot still and i am 13 weeks pregnant, i still get them i also get a small twitchy pain down there too.
I was tired had sore boobs and i knew i was pregnant! had something tell me in my head and i did question it as i thought i wasnt lucky enough in life to get pregnant the first time i tried! but i was! and for once lately life was treating me kindly!! so it can do that to u too!
So if u feel u r pregnant then do a test! i know it may be fustrating if it was neg but its the only way to find out!
hope its pos! good luck!!