I was texting my sister bout a concert and my keyboard started the word when after the "h" was pressed it made a "ltqpeb" and sent the message. I rebooted the phone and took out the battery for a few minutes. Put it back in and my phone boot into safe mood. Nothing samed to be acting up this time so I restarted the phone. Now I cant draw my lock-code thing. It starts ok then goes across the phone to look like a mess. I got back into my messages to send her what I wanted to say after calling voicemail several times. so the message sent with the smile emoticon as a space. Because the spacebar now means :-). On a side note it makes a dial-up kinda noise when it boots up and my widgets are not on the homesceen now. It has not been near any water or moisture unless it is acting up from the time it was in my pants when I took a shower after work.
Also if it is broken do I take the phone to best buy (where I go it) or the sprint store down the road?
I have seen on the capacitive screens where on a rare basis will temporary short out if there is an disruption, change or otherwise just doesn't like the sort of power it is getting. Usually this can be solved just as you discovered by unplugging and plugging it back in, but if it becomes a pattern of occurring, I honestly would recommend checking to see if its a problem with the cable first.