I changed light switches and now my hall way lights (three way switches) don't work and also one bathroom and the original light don't work now. I put in a single pole light switch and it seemed to work, now it doesn't. I have two black wires and a red wire coming to the outlet that doesn't work and I think is affecting the others.

You are not clear in your description. Take a deep breath and try again. Did you replace both 3-way switches? Where did the single-pole switch go? Is there an outlet not working or do you mean a switch? Was it a switched outlet? Why did you replace the switches in the first place?