gaining weight and fatigue

I have been on PTU for three month with my levels going towards the normal level. I know the endo said it would be a good 6 months before I would start to feel like myself again, but I have been gaining weight and feeling more tired. If i understood the endo correctly she said I don't have hypo antibodies. Has anyone else gained weight with graves and became more tired as it was getting better. I know I am not a forth active as I was before being diagnosed so I chalk the extra lbs up to lack of activity. I was diagnosed 1 year after my 1st child.