i feel pregnant 4 and half weeks late and negative results?

i have very irregular periods, always have, but i had unprotected sex with my boyfriend on march 1st, he pulled out but said he might have cummed inside of me. ive been waiting and today is the 5th of april, i have taken 3 tests all at home and it came out negative, although one showed a faint line next to it,? i have the symptoms, realy tired, sore breasts,cramping gaining wieght, and eating very much more then usual. and mood swings. but also its wierd as it sounds, but i usalu sleep on my stomach and i cant anymore its not comfortable .. its almost like my stomcha is like getting a little harder.. i feel pregnant. like something is different? and its hard cause i dont knoe when to even expect my periods there never the same. its just anytime it feels like coming.


anyone in the same boat.