LG Viewty problem?

Hi, I have been having a few issues with my text messages. I am creating a new message and then it takes forever to send. When I go to see what is wrong in the out box it is actually sending an old message thats in my sent box?! I have also noticed several of my old texts have now got additional messages tagged on the bottom. I admit I am a bit of a text message hoarder, so this may be the issue but not sure? My phone is a LG Viewty and about to run out of its contract in a few weeks - it must know I am going to replace it soon... ha ha! But I do still want to use this phone as its been good to me...