I agree with all the previous poster, except that there is one thing that makes my ears perk up just a little -- when you say "all my fish", like, how much fish per how much tank are we talking, here?
A 2 month old tank is still really quite 'young' and not going to be able to gracefully and bombproofly handle all *that* much fish, especially if you've got other things going on e.g. plants decaying.
If you have already loaded the tank to half 'capacity' or more, you would definitely want to monitor water conditions over the next month (ideally testing all 3 kinds of N separately if you really want a good understanding of what is going on).
At the least I would suggest vacuuming out any remaining dead plant bits in the tank, and not adding anymore fish for a few *months*. The more fully you let a tank run in before you populate it seriously, the more stable it will be.
If your plants are dying you will also want to address that. What kind of plants and what kind of lighting -- there are hardly any plants that will do well under the 'standard' aquarium hood lights (single, non high intensity fluorescent bulb) - basically just Anubias, java moss, java fern, and also some cryptocorynes if tiy have the water chemistry right. Anything else will be a quick or slow trip to decay city, and is not good for your tank or fish.
(I have occasionally also had trouble with fast-growing plants under moderately high light having parts languish or die in a very new tank, I assume from lack of nutrients for the amount of growth they are 'programmed' for. )
Good luck,
Pat