Yes I had sexual intercourse June 19 missed my period for June an half of July.. I'm having really bad cramps sharp pains in my stomach and I can't sleep at night because of these pains.Some parts of my stomach feel a little bit hard.I'm wondering could I be pregnant

It's possible you are. Try taking a pregnancy test using first morning urine.

I would make an appointment to see your doctor. Yes you could be pregnant, you could also be in the early stages of a miscarriage. You could also be under stress or unwell and therefore have just missed your periods, but I would be making an appointment to be on the safe side.