Hi, over the last week I've been experiencing a bad pain in my upper left thigh (near my hip and groin area). The pain is almost constant but sometimes mild. However, at other times it is severe enough to make walking or lifting the leg very difficult. There are also times (about 5 times throughout the day) where it is extremely painful to sit down. When I force myself to do so anyway the pain shoots down from my upper thigh to my knee cap and is excruciating. However once I've been seated for a few minutes it goes back to mild. I sustained no injury or trauma to the area that I'm aware of. I'm a 24 year old female, a little overweight but otherwise healthy, although I did have a laparoscopic surgery at the end of March. What is causing this pain?