Sudden problem with zooming? (Confused!)

Alright, I’m not sure what is causing this to happen nor how to remedy it, I can only hope someone here knows what I’m talking about.

This has occured twice now.

I zoom in and out of my pics with the mouse wheel as I’m sure most do. This is what I’m currently working on (don’t know if this will help at all):

I created a circle for the leg, and extruded it upwards a bit. Immediately afterwards, my zooming got funky. As soon as I zoom near the object, the zoom speed gets proportionately slower the closer I get to the object, until it seems to not move at all. I can zoom out, slowly at first, then back to a more normal speed.

This occured also with a lighthouse I was trying to model. I have NO IDEA why this is happening or what to do about it.

Can anyone help?

Just hit 5 on your Numpad to go to Orthographic mode. It happens in Perspective mode.