Hella P indeed.
I've had the shoulder button problem with every Nintendo handheld since the SP. If it's still under warranty (look up your serial number at support.nintendo.com), send it in and get it repaired, and hope that the shoulder buttons go out again within a year so it'll be under warranty again (they re-warrantize them when they fix them). If not, it might run you $60 or so, but it's still worth it.
Once it's fixed, do make sure you're keeping it clean and not putting sandwiches in it (like my older sisters did with our NES), and maybe consider not putting it in your pocket all the time (I think that might be the cause of the shoulder button problem).