Mechanics Vs. Velocity

Hello, I’m a 12 year old pitcher(4’ 10”) and am recovering from arm soreness. I took two weeks off of pitching and just pitched 20 pitches last night in Little League. I did 1 2/3 IP, 0 H, 3 K’s, 0 BB. I asked my friends from the other team that also play AAU with me and they said my velocity was down about 3-5 MPH, but my mechanics looked much better. Do you think I should focus on using the right mechanics when pitching, focus on pitching like I did before that put a lot of stress on my arm to throw a little harder, or do you think my velocity was down because it was my first time pitching in a couple weeks? Any feedback is great appreciated! Thanks!

Video would be the most helpful thing but I guess the best answer I can give without video is use proper mechanics to try and avoid injuries.