I have some problems with eating. even before swallowing, i get like a gag reflex. what can i do? because of this problem i have lost some weight.

Swallowing problem : Wondering how long this has been going on and whether you have been under any new stresses. It might be useful to see a Speech therapist for a swallow evaluation to rule out vocal cord dysfunction. Your primary doctor can refer you after checking for other causes.

Dysphagia: Definitely worth investigating specifically with weight loss. A variety of possibilities from an eating disorder to esophageal structural or functional disorders. Talk to your doc for a visit and starting workup.

Agree with Dr. M: A speech pathologist, despite the name, is an appropriate professional to evaluate your issue. Have a healthy diet, exercise 30 minutes/day, drink plenty of water, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/. Get HPV vaccine. Wish you good health!