It should go away in about a week if you don't shoot anymore... I now use a browning vest with the g2 pad and I don't get any bruises. My wife was worried that I was up to no good when I first started shooting and came home with a big bruise(poor fitting gun, and poorer technique).
She quickly found out how I got the bruise once she shot her first round of trap.
I started shooting in 1970, I still have a bruise and skin discoloration from where I placed my butt pad on my shoulder to this very day. Since I do not shoot as much as I did years ago, it no longer hurts and the discoloration has somewhat faded.
I don't have any bruises from shooting. I use to use an extra recoil pad in my vest but after a Nora Ross clinic she changed my gun mount slightly and got me to pull the stock more firmly into the shoulder pocket. Don't notice recoil now so don't put the extra pad in my vest any more. My BT has a GraCoil recoil reducer and the new gun mount method I use has my head slightly turned into the stock and more firmly planted. I had to go from the lightest spring setting to the heaviest after changing my gun hold because the stock was scrubbing my cheek. My Citori only has comb adjustment, no recoil system. I don't notice recoil with the Citori any more than I do with the BT. I'm also shooting 1 1/8 oz 3 DE loads. Your question has me wondering if gun mount changes might eliminate the bruise.
It will fade, but the blood turns into hemosiderin (iron containing protein) which will persist, as will the soon to be acquired flinch. Really. Hakuna: If you are not taking fish oil, aspirin, or another 'blood thinner', you should have your platelet count checked.
A professional gun fitting seems to be in order!!! I would have him install a Kick-ezz recoil pad while he's working on it as well. The kick-ezz pad is the first thing I do to a new gun, before I even shoot it. Good Luck and break em all. Jeff
unless your one of them folks that just bruise at anything lol , if your getting bruised something isnt right. maybe a little rasberry after a few months of not shooting, but you shouldnt be continually getting bruised from shooting.
So I live on anticoagulants for heart condition and I don't bruise when shooting and neither should you.
You have a mount issue, a gun fit issue, or both. In the former, I would look to see if you mount the gun firmly in your shoulder pocket to prevent it accelerating into you on recoil. With regard to gun fit, lots of candidate issues but pitch, drop at heel, and toe out come to mind with pitch being often the least understood and sometime causing the most pain/discomfort.