Yea, I would try to go few gauges thinner... I used to pin with 21G or 22G all the time to every spot I was using, and also ended up with fair amount of scartissue in those sites. If you are like me and think 25G is abit too thin, (they work well for some injections, but are not very convenient when injecting 2-3 cc's/ml's of oil) I would def. rec. to give a try to 23G, good option between too big, and too thin. They have served me well, and now I use my old 22G pins only for drawing.