The penis will often shrink after sessions involving length, more so when done flaccid. I'm not sure what the exact reason is for this, but its something we all face, or have faced.
Try to use the sleeves, it may be possible that they dont fit exact after such a session due to the shrinkage, in that case, try to ensure the penis is warm .. I find I need to use the tighter
sleeve when I go outside, due to the cold, which I never would have thought of doing inside the house, where I use the looser
sleeve.
If you got a heat lamp, give it a go after sessions, or the traditional old way
face cloth soaked in hot water, then ring it out, and wrap it around your stuff.