Well, I will just add that I know how you feel.
I 2nd, 3rd, and 4th, the suggestion of writing your thoughts and feelings down in an anger journal. You don't have the money for a therapist right now, but they would probably ask you to do the same thing. Don't show your papers to anyone, just get it out on paper. It really helps a lot. Don't obsess about your past and upbringing or your past mistakes. Just write your angry thoughts down.
Medications can lesson anxiety or depression, but I believe the root causes of those emotions are what your belief system is about yourself. Rather than take medications, ask yourself:
Do you think that if your kids misbehave, that you are a bad parent/person? Think a lot about that question. A lot of anger at kids can come from not being able to control them and freaking when they are not perfect. Why is it a threat to you that they mess up? Are you taking it personally?
Try getting up before the kids and doing deep breathing Qi Gong exercises. It sounds crazy but not at all. I got a book from the library on how to do them because I get anxiety and depression. Chinese believe that when you have these emotions, they can make your body sick and all your systems go off kilter. You need balance in your life from the business and craziness of being a mom.
Try to go out on a nature stroll every day. Nature can calm your spirit.
Religion helps too, like praying to God and trying to give him your anger and let him take care of you.
Cheers,
Marci