Default [Q] Contacts receiving sms/mms that I never sent!

People are telling me they received the following message from me:
The media content was not included due to a picture resolution or message size restriction.
But I have not sent out any sms or mms to them at all today!!! What is going on??? Could an app be messing with my phone?
I have Snapchat, Twitter, Facebook, what's app, Squareit, Mr. Number, Instagram, and some games. Should I uninstall any of these? This is extremely important, as I have business contacts in my phone! Help me please!!