I pulled my left bicep back in April and carefully nursed it back to normal working condition. When I pulled it, I was going up in weight in my bicep curl by 2 lbs. It felt good, not like I was straining, but it obviously got injured. Now, last week, I went up to that weight again, after waiting for months to try it and boom, pulled it again. Why is this happening when I'm not even struggling with the weight. I mean, it's a challenge, but not something that should cause injury. Does this mean that after months it wasn't really healed? Or, am I doomed to stay at the lesser weight?