I am 50 and have been riding for 35 years with 10 years in bike shops. That bike it too small for you. The bars are too low, causing you to put more weight on your hands. You can ease this with a longer stem that rises more, but the store should have sold you the right bike in the first place. Your hands may go a little numb sometimes, but shouldn't hurt. Your butt will hurt until you get in better shape and firm up those muscles...