Is one time premature ejaculation something i should worry about?

No. 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.

No. And dont think too much about it. As you gain confidence and 3experience it might disappear. But pl be careful and take precautions to avoid VD. Wishing you good health

You are young and inexperienced and no doubt are worried. As time goes on you will be able to control your desires. The most important concern you should worry about is avoiding any STD'S by practicing safe sex.