I have a Samsung S5. I have noticed that sometimes when I go to send a text message, that there is a text message listed that I didn't send. I am using the text message software that came with the phone. I haven't added any apps to phone in awhile. On the list of the conversations, I would see a name and it says muti media message. So when I click on the message to see what it is, the message is blank. The names are random names from my contacts and never people that I have contacted in the last year, so I know I didn't mistakenly send a text message. Could my phone be hacked or have a bug?