kick my butt

In just over 13 weeks I will be going to Cambodia to cycle for charity for 5 days. At the moment I weigh in at 227, after losing 32lbs in the last 4 months. However for the past month I have kinda stalled and not pushed myself like I did at the start.
I have given myself a good talking to, and started taking my daily vitamins and extra vit D that will hopefully make me cheer up and want to get going again.
I need to increase my exercise and eat cleaner. I did it when I first joined here and know what and how to do it. What I am lacking is the get up and go. In a ideal world I would lobe to lose another 32lbs before going to Cambodia, but since I am a realist I am aiming at 20lbs. To drop 2 dress sizes will be perfect too. The idea of of squeezing into the plane seat is a scary thought so shaving off them inches is needed.