I'm more broken than you

[cranefly]

I've heard that unexplicable injuries is a sign of addiction. But I've been very clean lately. 

I've found a centimeter cut on on the pad of my right thumb...

I don't think there's a need to worry about addiction.  This is more likely a sign of alien abduction.
For whatever reason, aliens are fascinated by human thumbs.  They're always pulling them off, doing experiments, then putting them back on.  Sometimes when putting them back on, they get them reversed.

You might want to check for that.  It can be hard to tell.