On the bruises: children are pretty sturdy and flexible. They bump into things all the time and it's pretty common for their arms and especially legs to be littered with bruises. If your son is a tough kid, he might not even pay attention when he drops something on his foot but just continue playing.

Think about how he usually acts when he hurts himself. Does he ignore it? Is he a kid that comes crying at the first thing? If it helps you, write down your experiences with his reaction on different kinds of accidents. You're likely to find out that if he really needs you to comfort him, you or your husband have been there.

A good parent is a disciplinarian. By creating safe boundaries and protecting a child from itself, you enable it to discover itself and the world safely. But many people here are allergic to the word 'disciplinarian' because they relate it directly to abuse they suffered. It's ok to feel like a disciplinarian, because it means you care for your child and are concerned with its safety and well being.

If you are concerned you don't have a good arsenal of reactions to situations you are confronted with: if you are unhappy with how you reacted to a situation, talk about it with your husband and/or google it. There are a million moms and dads likely to have faced the same issue and many of them (fortunately) put their questions on the internet. That way you can research different ways of handling things and you'll feel more prepared next time. It helps with the anxiety :) (or at least, it helped me and I start doing it more and more :) )

There is also a certain style of parenting called Triple P : Positive Parenting Program. This is very helpful because it teaches a way to think about parenting, which can be applies very diversely.

Anyway, you're not alone! :)