Is it normal i hump my pillow?

ok, so it all started when i was 12 3/4. I was sitting in my bed in my room. my mom was in the basement and my brother was using the computer. So i was just looking at my pillow and decided i wanted to hump it to see what it was like.so i put it on my bed and put it between my legs. i started to rub it up and down my vagina. it felt so good and then i pretended it was my crush from school doing it with me. Then i had an orgasm with my pillow!? i hadnt felt that before, but all i knew is that it felt really good. i've done it for about half a year and nobody in my family or friends have found out. Im single and i have never had a boyfriend in my life. Is this normal?