I had sex last nite, was on top. left hip hurts so bad especially putting weight on it, bending, walking, flexing muscle near it. what did i do?

Hip or back strain: It is very possible that you may have strained dome muscle in your hip or may have activated some old bursitis in your hip . OR you may have pulled your back out and what you are feeling is referred pain from your back into your hip . Try rest , some Anti inflammatory medications or use some pain pads such as Salonpas OTC if it continues more than a week , seek medical attention .