Need Help With Snake's Reaction to Being Pet

[Toopel]

I have had my BP for 4 years now, they're rather docile and have only bitten me 4 times. I am working on rehabbing them right now, and taking them out more often is part of that. However, when I don't take them out right away and pet them so that they can get accustomed to my hand they kind of "hit" me with their body, I'll provide a video here: https://www.youtube.com/watch?v=2rFG...ature=youtu.be

I really need help, I can't find advice for this anywhere online and I'd really like to know if this is normal behavior or if something is wrong with them.