Well I deadlifted this morning for the 2nd week in a row after taking a few months off. I focused as much as I possibly could on my form and reped some pretty heavy weight for me. Now I noticed after doing the lifts that I had more soreness in my middle back RIGHT erector spine muscle and didn't feel much on the left side. Now I just have some weakness there but more weakness or soreness I guess is in my lower right back.

Now could this be due to bad form? forcing the weight a little too high? or something else? I just want to prevent a injury before I do something crazy.