Is it normal for my stomach to be hard 5 days after losing virginity? and not being able to poop?

The firmness of your abdomen is more likely related to significant constipation & bloating rather than to losing your virginity. If you have an urge but can't move your bowels, work from below by inserting a glycerine rectal suppository, or dulcolax suppository or a Fleets enema. If you have no urge,take a laxative like miralax or milk of magnesia. Drink lots of fluids,eat fiber,exercise regularly