What is causing pain in my elbow; where my joints are? it hurts when i lift heavy stuff.

Tennis elbow: Pain on the outside of elbow with lifting in thirty something is likely a musculoskeletal problem related to repetative stress or even one extraordinary mechanical event. The medical name is lateral epicondylitis aka "tennis elbow". Rest, warm soaks, avoidance of repetative elbow use, & otc elbow strap might help. Persistence suggests need for doctor visit. Osteopath or physiatrist best.