I think I can see what has happened by reading all the comments. Text has become a verb because it has replaced the longer word it once described, message. You messaged a message, and now you texted a text (message). So, instead of saying text messaged you, we have shortened it to texted and created a verb from an adjective, along with a past tense. However, text has always been a noun on its own. It may be similar to the word phone. You can phone someone, or talk to someone on the phone. Then, you have phoned them.