Yeah, just takes about a week to dissipate and can sometimes turn into a painful sterile abscess. Shouldn't require anti biotics but can become really painful and red. I've had it happen a few times. Didn't take any anti biotics, just needed to make sure it didn't get hurt. My fiance is like the Tasmanian Devil though and she always managed to smash into them - HOLY FUCK does it hurt!!!
I have a bad habit of cramping up when hitting glutes and have done a few shallow injections. It really sucks with the oil sits between the muscle and fat, or goes directly in the fat. Even with most UGL stuff though it'll probably just go away in a week. Be careful and just use longer needles in the future though. That's what I do and it's good to go.