Pain after operation

Last Thursday I had lump removed, and 4 lymph nodes. I am in so much pain.my armpit aches so does arm.i am taking paracetamol. But can not have ibuprofen as I am on Ivf injections to try and save eggs. As I will be having chemo, radiotherapy and herceptin soon. I'm dreading all the treatments. Can anyone tell me how long this pain lasts?