Lumpectomy and Sentinel lymph node

Hi my name is Cheryl I had a lumpectomy and sentinel lymph node 3 weeks ago at first it was fine wasn’t in that much pain so after about a week I started cutting my codeine down to only 2 at night as couldn’t deal with the constipation. I had my sterile strips removed yesterday and since this I’m getting stabbing pains in nipple and under arm , of course researched it and meant to be normal ? I ordered this cream called OUCH as heard ladies raving about it , I’ve applied it around my wound NOT directly on wound only been 2 days so probably not kicked in yet ( really smells bad) also heard that cabbage leafs inserted in Bra is meant to be good ! Not sure if anyone out there going through the same as me and can give some advice on the stabbing pain. I also noticed I’m walking like I’ve got a hunchback as scared to stick my boobs out and curving at the shoulders which is given me pins and needles in the neck And can’t raise my arm to high coz of the cut under arm . Why am I reading it takes a few weeks to recover as I feel maybe another few weeks I hope to be fine !!!!