My wife gets this, except she gets it from her thigh. Yes, it can hurt and hurt badly because a lot of the fat cells die. Hence the misshapen nature of your boob. But in my wife's case, every time it begins to hurt, she gets them refilled and a little more cells survive each time and her boob no longer looks misshapen. She's had the op 4 times and might need another one depending on the fat cell death. It's the lack of fat cells that are probably hurting. Most folk usually require at least 2-3 refills before you have enough fat cells. All of the above is what my wife has been told a few times from her surgeon.