This makes total sense to me.

You're hanging out in a motel, you're shooting up heroin, and you think you accidentally inject air into your veins.

Of course the logical thing to do is to run to Denny's and try to cut your own arm off.

Also, I'm glad they closed the Denny's to clean up. That much blood on the counter would definitely ruin my enjoyment of a delicious Moons Over My Hammy.