My car is making this loud noise, sounds like something is spinning?

On my way to a concert last night, a car almost hit me on my right side, so I had to make a hard left, then almost a minute later, there was this loud spinning, whipping noise. It's hard to explain. It was so loud that I could hardly have a conversation with my friend who was right next to me.

We got to the concert, parked in the parking garage, which I was scared to do because of what just happened and after the concert, the car started right up and the noise was still there. At speeds between 25-45 the noise is horrible, but going 55, it wasn't as loud and I could actually hear what was going on.

My dad is going to come and look at it after he gets out of work today, but does anyone have an idea of what it could be?

Maybe something rubbing against something, or my brakes? I was thinking, great my belt is going to break but I made it home just fine.

Thanks.

Oh almost forgot, I drive a 99 Cutlass.