The choice is up to you. But as along as you shower regularly, you are not going to smell and no one is going to know that you do it (even considering that about 90% of all males do). Masturbation is compltely safe and won't have any affect on the size of your penis. Chances are that the one time you just had a stronger erection, or you measured differently.

Dont worry about the smell in my opinion. Just dont cum all up in ur pants and ull be fine man. Good luck, and if you could check otu ym thread and give me some feedback.