Why am I so tired after a minor operation?

I had a tummy tuck with double hernia and muscle repair 11 months ago. I unfortunately had a bad bleed which resulted in me being rushed back to theatre for an emergency operation to fix it. As my surgeon had to go in quickly it left me with lumps on both ends of my scar. It took me 5 months to feel normal again, even the slightest thing made me tired for ages. I went back to my surgeon 4 days ago and under local he corrected the lumps and the incision was extended by about 2 inches either side.. As the local wore off the incisions became quite painful and I've become totally exhausted ever since. I feel tired all day and although I'm in pain from the surgery its obviously nowhere near as bad as last time and I didn't even have a general. Is it normal to feel this tired after something quite minor?