Thanks for the suggestions! I'll try with slightly larger diapers and from another brand (the ones I'm wearing now are a bit too tight, but it was my first time buying diapers). If it doesn't work as expected, I'll then try to wrap it with a small diaper, as it was suggested.
I don't feel like jerking off first thing in the morning. I'd prefer to stay sleepy in bed for a while, possibly peeing myself, and then wake up and change.
Point it down usually works, but it's really uncomfortable, and sometimes even painful.