Don't open the door

Maybe you wound up in here because you've developed the power to teleport. Attempt to teleport out.

While you're lying on the floor, you close your eyes and try to remember how you got here. Maybe you accidentally teleported yourself here. These things can happen. You don't remember it but you're pretty sure you know someone who heard about a guy who had a cousin who could teleport from his bedroom to his living room.
You slow down your breathing and focus on... nothing, because you can't remember any place beside this damn room. Fuck. You don't know how teleportation works but you're pretty sure you need to know where you want to teleport.
This won't work.

>0002? Well that's concerning. Not so much that your not 0001, but that whoever put you here thought they probably would go through a lot more than two subjects.

>Check for a nice big shard of glass. Something you could scrape messages in the wall with. Just because you start off this mess without any idea what to do doesn't mean the schmuck after you has to be unaware of whatever trouble happens.

Make sure that you scratch what you are going to do before you do it, and the results after you do it, and sign your messages. If you are incapacitated, future people won't be able to read what you don't write.

also be polite and leave the glass behind.

You think about the tattoo on your chest. Assuming the person who put you here is counting the people they capture, they are planning for way more people than just 2. Maybe you won't get out, but you could help others by telling them about your experiences.
You get up and grab the biggest shard of glass you could find, then look for a place to write messages... It needs to be somewhere you know people will see it and easy to scrape using glass. Somewhere like... the door.
You remove the piece of paper that's still taped to the door and begin engraving your message :

Hey guys ! 0002 here !
Door is locked.
Cannot kick down door.
No exit in walls/floor.
Teleportation not available.
Walls should be baltic gray.

You feel good about yourself. If you keep on being this helpful to people you're going to have the BEST karma !