It takes months and months to recover from major abdominal surgery - all sorts of important internal muscles are cut. I had a nephrectomy operation in late 2018 (MRI scans during prostate cancer diagnosis revealed a kidney tumour!), which is an operation that cuts the same muscles, and it was a good 6 months before I was physically back to normal again. Take it easy - 7 weeks is relatively early days.
Best wishes,
Chris