Sharp pain in left side of groin only when i'm sleeping?

Doctor can evaluate: Pains in the groin, legs, or hips occurring only while sleeping may be due to the lying-in-bed position. A thorough exam of the muscles and joints in and around the hips may give some clues (one can see a primary care doctor or a physiatrist - a physical medicine and rehabilitation doctor). The primary doctor can also look for problems with genitals, intestines, hernias, blood circulation, etc...

Groin pain: Groin pain is concerning for a hernia. Perhaps there is something about the position that you are in that exacerbates the issue - although hernias are more commonly noticed when there are increases in intra-abdominal pressure, like when straining. If the problem is consistent over time, then it should be evaluated.