Help With Dyslexia...Advice Would Be Great!?

I feel so dumb when I say, "Oh, sorry! I'm Dyslexic!" when I do something wrong or when I feel awkward in a situation in which I can't do something. Plus, when I say it people look at me funny or say ,"What does that have to do with this...?" Because they think it only concerns reading things backwards. There's been a lot of instances when I get directions wrong, or can't understand some things. I was even told once, "It's not an excuse for everything!" When I was having difficulty one day in class with memorizing. Instead of lashing out on them (LOL) or being a jerk about it, what can I say or do?