Stinging feeling inside penis

For the past two days my penis has been feeling rather uncomfortable. Im 18 and not sexually active so that rules out STD's but i do masterbate alot. i noticed it stung a bit after taking a piss about friday so i decided to squeeze the penis (probs a mistake) and since sunday night it has been hurting alot. Yesterday it was agony but today its not quite so bad and have been able to masturbate twice (too much info, right?) however for teh past 5 days i have been drinking a ridiculous amount. Anyway a;ready booked an appoitment with the doc for next week. Not to worried about this just yet cus its only been in discomfort for a few days, may it be a urinary infection? Anyway its feels as if there is something stuck in there at times such as water or something.

Would appreaciate any info or how to make the discomfort going away a tad bit.