Is it normal to kiss like in the scene from spiderman?

If yall remember (or have ever seen) Spiderman, then you probably remember the scene where Mj kisses Peter while he's dangling upside down.
Me and my girlfriend and have kissed like this before a few times, and it really turns me on. I'll be on the couch and turn myself upside down while she'll be on kneeled the floor, and we do the kiss. She thinks it's funny. But i think it's so hot. It gives me this huge, almost dancing, boner. It just really turns me on big time, I don't know how else to explain it..

Is it normal to be turned on so much by that? I myself don't understand why it does, because really the only difference there from a normal kiss is that i'm upside down.