I've went to dr. and he told me that i have a beginning of golf elbow. what is it ? what precautions i should take? and when can i go bk to the gym?

Opposite of: Tennis elbow .Inflamed soft tissue around the epicondyle ( inside/golfers, outside/tennis).One needs to stop the activity that is causing the inflammation in the first place .This likely involves some mechanical adjustment in form.Give it time to heal...No more pain.

Medial Epicondylitis: Golfer's elbow is medically termed medial epicondylitis and results from a strain on the tendon on the inside of the elbow that usually results from repeated actions similar to a golf swing. I would recommend anti-inflammatories such as otc Ibuprofen or Naproxen and rest the elbow for about 5-7 days. Gently get back into working out but pay attention to any problems and rest again if needed.

Rest the elbow: Golfer's elbow is a kind of tndon inflammation. Usually due to repetitive trauma to the tendons attached to the inside of the elbow. Avoiding strenuous elbow movements, use of ice packs and anti-inflammatory agents usually resolve the condition in few weeks. If not, then a corticosteroid injection around the inflamed tendon relieves. Surgery is rarely needed.