A note on anti-depressants:

They aren't uppers, they are not designed to make you feel happy, they arent designed to get you a high. They are mood levelers, they take you from depression to flat effect, thats it. Its entirely up to you to pull yourself up the rest of the way, but they keep you operating. They wont fully kick in for a few weeks, and you get to pass through the dangerous levels of depression, the levels where you actually are capable of making plans and following through with them, but you're still emotionally messed up. This leads to bad behavior, including suicide, if it isn't something that goes through your mind you're probably safe, but this is the area where people also do drugs and break laws, because they think it might be a good idea.

Mind altering drugs are just that, mind altering, they either stop your brain from reabsorbing chemicals that are released or they increase production of said chemicals.

I'm used to this level of depression, personally, and I'm used to the level you described, and I'm used to extreme emotional highs. Its always great being manic depressive. Drugs arent always needed and should only be used to get you back to functioning levels, if your depression is so bad it is affecting your work life.