Need motivation

I just finished a 3-mile run and you would have thought it was a full marathon. Running used to be as easy for me as doing anything else but lately feels like such an effort. I know it's a result of me just feeling sluggish after gaining weight and I need something to get me motivated to start losing! I'm thinking of going strictly gluten free or even paleo but am scared I won't be able to stick to it. Anyone have any suggestions as to what worked for them as a kickstart for losing weight or want to join me to keep each other motivated and on track?

Feel free to add me!