I live in a condo and have an electric hot water heater. Every time I need to wash clothes or use the dishwasher, the hot water never comes out. However, when I turn the hot water on in the bathroom upstairs in the tub, it will be hot for 2 minutes then turn cold the entire time. The hot water works fine in the kitchen sink. What could be the problem? I have no clue.

Example: for the first time today, I arrived home from work, turn the shower on, the water starts hot and then turns cold after 2 minutes. (mind you this was the first time today that I demanded water)

Likely your bottom element is out. Or the dip tube.

doug238 is right but I always change out the bottom and top element. Remember to drain the water and don't dry start it... note

A top element typically lasts twice as long as the bottom element. I usually only change the bottom on the first trip. If I go back and find they have previously done this I change both explaining why.

If you have had any trash show up in your aerators the first thing to check is the dip tube that mentioned above. Unless you have a very small water heater, if so then check the elements, if there are two, if not you will only have one element at the bottom of the heater.