Had a wet dream and humped my pillow, apparently.

I had a wet dream last night and must've grabbed my pillow and started humping it. I woke up to find the evidence of my deed deposited there. What's surprising is that I'm 63 years old. Been single for five years. No sex or even jerking off for close to a month. So at my age and recent lack of any sexual activity, will this wet dream pillow humping become normal for me? Kind of made me feel like a 15 year old.