That is awesome you have lost 50 pounds. Maybe ask your consultant from Weight Watchers.
I would continue to log your info on spark people and maybe make some adjustments on your goals and settings for your trackers.
If you feel good and don't feel hungry all the time and your have energy. I would say your doing great. Soon you will have to do the program on your own when your done so be prepared for the after the WW.
Keep up the good work and try not to beat yourself up over it. Work on the positive and what you can control.