Jenn, kudos on your walk. I have to plump up my veins for bloodwork, too, even when I consistently drink 64 oz. per day. But I do have large veins on top of my hands and it doesn't bother me if they resort to taking blood from there. Wishing you really good results.
Age 68, 5 feet tall
Highest weight ever in the fall of 2010 246 lbs.
FitDay starting weight 1/17/2011 240 lbs.
Weight 8/14/2014 lowest in a long time 224.2
Weight 9/23/2014 doctor visit 233
Weight 11/14/2014 228.8