Hey, apologies if this has been brought up before. I did search and found a ton on deadlifting and back pain, but not this specific question. Although it's possible I missed it, I'm getting too close to bed time.
Anyway, I just bought a barbell this weekend. Prior to this (two weeks) I was doing my deadlifts with a short triceps bar and only 136 lbs on it. Not very challenging and I'm sure that due to having to keep my hands close together my form wasn't proper. I guess closer to a sumo deadlift. Now that I have the barbell, I'm able to do them with (I hope) proper form and have increased the weight to 210 lbs. I want much more, but need to buy more plates. So I'm doing this 15 reps x 3 sets. I usually need a 30 second breather after the 10th rep and maybe a second breather after that. Then I space about two minutes with stretching and hit the next set.
When I was using the triceps bar to do this movement, the first night after I did it I woke up in the middle of the night with a shocking pain going from my lower back up into my shoulder blades. Lasted a few minutes, but then I was fine. No more pain. The second week, I just had a stiffness in my back immediately after my workout, but the next day no issues really.
Tonight I used the barbell with the greater weight for the first time. I notice now a stiffness, not pain exactly, in my lower back. It's not really bad, but I'm just wondering if this is normal? I'm worried mostly because I've injured my back more than once at work from lifting too much improperly. Having back pain hinders my ability to perform my job, which involves heavy and awkward lifting, so I need to be careful.
Does everyone's back stiffen up after deadlifts? Could it be bad form? Too many reps? Just a need to get used to it? I'd just like to know before I either give up on what could be a useful exercise or continue what could lead to a serious back injury.
Oh, and I wanted to add this: I've read both that the bar should be mid-shin and that it's better for the bar to be lower to increase range of motion. Seems like less stress on the back if the bar is higher, but at the sacrifice of effectiveness of the exercise. Is this an issue? I'm doing it with smaller plates (25's, 10's, and 5's) until I can afford to get some bigger ones.