Night time erections

I'm using Batmate Xtreme 40 for a year now mostly for the thickness with some really good results i thought to try also a stretching device. PF seemed the best choice because it could be wore on night time but... This is the third day i used it now, during the evening is ok i even wrapped some cloth around the base ring to make it stop pulling my hair and pinching but in bed when sleeping i'm getting some really powerful erection and even if i use the large bell my penis head feel crushed in a very painful way. My penis head is 16cm and the penis is 16.5cm in girth fully erected. Does anybody have a solution for this ? I have to give up using it in the night time ?