Humping ...

Ever since I was a little girl I hummed.. I would put my arms in between my legs and just start humping them... I have never told any one this, of course my family knew about it cause I would do it all the time as a kid but didn't know what it meant.. My mom always told me to go to my room if I was going to do it. They all think I've grown out of it, but I haven't. I'll still turn on porn and hump and I'm 20 years old.... Obviously I don't do it all the time .. I'm so emberessed about this but I was wondering if I'm the only one that does this?