Don't know where to start. Survived child abuse and spousal abuse. Now, believe it or not, it's my brother.

Here's' the situation: My mom is ill and my brother and I are the ones handling the situation. He doesn't like me and it goes way back. I have tried to make things work with him, but he isn't having it. I even wrote a letter a while back saying, whatever I may have done to you, I don't know what it is, but I apologize and I love you. Let's work together as a family.

Here is what he does. He has this way of ordering me around, I think. I will give an example:
He emailed me 16 times about a situation going on at my Mom's house all in a ROW, over a, what 20 minutes time period. The details are not important. The point is I did not understand what he was trying to tell me regarding an issue with her phone, which she needs because she is elderly and sick. So we went back and forth with me asking questions and finally I said "please call my cell phone. I am not understanding you. So he sends me this email, the 16th one saying "look, this thing is really simple, and I don't have the time to call you on the phone over it". Well, I felt my request wasn't so awful and he was being sarcastic, so I did not answer. But, it is still bugging me.

I mean why can't he pick up the friggin phone and call me. He doesn't have the time? But he wants me to do something for him, or rather for my Mom? Is this controlling? Am I being too sensitive or what.
Thanks.