my friend, what I recommend is that you visit the game thread, because there you will find answers to pretty much every location you will get stuck on, as tons of people have been stuck there before you. However to exit the first hospital corridor can be challenging, but not really that difficult. If I remember correctly you need to poke around and examine everything. At some point you will hear a noise. I don't remember exactly what triggered it, but I think it was after I had been in all the rooms and examined the glass door. After you hear that noise, there will be a nurse in that empty examination room, and if you do things right with here, you will get the key to get out of there from her.
I know this is a bit fleeting but I can't remember exactly what to do, however as I said, if you look at the download page, there is a link to the game discussion, and as this is in the beginning of the game( this game is HUGE,) I assue you will get the answer to how to get to the next corridor in the beginning of the game discussion thread.