Phone turning on intermittently?

[355Nation]

For the past few evenings I've noticed my phone turn on sporadically...the only thing that is common each time is that the messaging application will open itself. I've tried to soft reset after it turns itself on and it will still turn on every 10-15 minutes...it's not a precise thing. I've gone through all my texts and have none that are showing as new...I'm really not sure what to do at this point. I haven't installed any new software for quite awhile, so I don't see a reason as to why it would be that...

Any help/incite is appreciated.

Oh, I should mention that when the phone "turns itself on" I mean that the screen comes on...no programs in the foreground, just the HTC home screen like you see in my signature. But the only program running will be messaging...even if I close it out, the screen still turns back on and the program opens...hope that helps.