So i always feel horny after the gym is this normal ? is it normal to masturbate in the shower after workingout? does it affect the muscle gain or losing fat ?

Masturbation will not do any harm. It will not interfere with muscle gain or fat loss. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Get HPV vaccine. Wish you good health!

Horniness varies considerably. People generally dont masturbate after workout. It will not affect your muscles or fat loss.