Is it normal that i masturbate without using my hands?

The very first time I masturbated, was when I lay with my belly down watching tv.. then a show named sexcetera appeared and as a young boy I got horny.. but while laying with my belly down I just started to thrust my penis against the bed, up and down till I reached climax. I never used my hands to masturbate since then. I always used a pillow or folded blankets. and recreated a tunnel effect similar to the vagina.. and I'm no virgin, had multiple girlfriends and loads of sex but this is my only way to 'pull' it off when I'm alone. I'm not mentally deranged or socially awkward. I do think about taking over the world so now and then, but that's all fun and game. but please let me know if there are others :)