Hello Julia, are you in the UK?
I had LIS and Fissurectomy in August and was sent home with only Ibuprofen and Flagyl, and was in severe pain for weeks, when I asked for pain relief I was told to buy Paracetamol, as if that would do anything!!
I asked if you was in the UK because it seems here they don't believe in pain relief after rectal surgery, I know a few people that have been sent home with only Ibuprofen, however, in the US they prescribe Vicodin and Percocet and some other painkillers, so if you live in the US you should be ok, I would take any pain relief for the first few weeks but we all have different pain thresholds.