Go Caper! Just cutting back the sugary drinks will make a big difference and eat small amounts often then you are less inclined to binge eat.
As the weight drops I am sure the pain will lessen. Over 10 years ago now, I had back problems, tired easily, had gall bladder problems resulting in cholecystitis, blood sugar swings and other health issues. I went to my Dr who said "You fit the classic profile for the 3 F's - you're fair, fat and 40."
It took me another 2 years to finally get off my backside (and the thought of being harpooned in Fiji at conference) and seriously do something about it but it was the best thing I ever did. These days I am much improved (apart from the past 12 months but that was an injury) and eating much more healthily (except when I attend conference )
Keep up the good work!