Chould it be that i am pregnant the top of my stomach is hard?

Unlikely: As pregnancy initially only effects the uterus, which early in pregnancy is still lower, "hard" upper abdomen likely is due to another process. Take a pregnancy test and see your doctor to then assess what might be going on for you. Please write down all symptoms (what you feel physically and emotionally), any related circumstances, time course, and what makes it better and worse.

Need more info: That is not one of the usual signs of an early pregnancy as you describe it. If you had unprotected sexual intercourse get a home pregnancy test done. If negative see your family physician. If positive see your ob-gyn.