Surgery has risks, but i have been in the operating room and they are VERY careful not to leave anything behind, they do like 3 counts before surgery and 3 counts after surgery of EVERYTHING, every tool, every gauze pad, everything. Of course there is always a risk of secondary infection, but they push antibiotics in before and after the surgery, so the risks are so minimal and from the sounds of it, you will do just fine.
Im glad to hear that it wasn't cancer, but cancer is treatable and curable! Ive also spent time in cancer offices and seen a ton of people successfully treated. And now they have drugs to go with it so you don't get all the nasty side effects from the radiation and chemo. Cancer treatement has come a long way.