Suggest Treatment For Urinary Problem After Masturabtion

I am 12, and I masturbate by pressing my testes with my hands, while laying on the ground, and "pushing" on my hands, and my penis is on my left thigh, is this irrregular? And when I pee, sometimes it feels like some pee is going back in, and it kind of feels like theres something inside my penis, like pee. Please help!