How big is the tank? What do you have stocked in it right now?
Just running the tank for a couple weeks without an ammonia source (ie fish or manually adding ammonia) doesn't do anything for the cycle. So unless you were adding an ammonia source, your cycle didn't start until you added fish.
Higher pH makes ammonia+nitrite more toxic. I wouldn't worry about it now though, any drastic change in pH will just stress the fish more. Most say not to worry about pH while cycling a tank anyways.
Any levels of ammonia+nitrite are unhealthy for the fish, but most will be okay if you keep the levels .25ppm or below. So it seems your nitrite (no2) is a too high. I would do a 50% water change and retest an hour later to see where it is. You may have to do another 50% change to get it around .25ppm. Make sure you use a good water conditioner (Prime is the best) and match the temperature. Are you using a product to detoxify ammonia+nitrite (Prime does that as well)? It seems like you are because nh4 is ammonium, which is the detoxified version of ammonia if I'm not mistaken. This will help make the cycling process a bit easier on the fish. Test strips are the least accurate way to test your water, so keep that in mind if that's what you are using. The API liquid kits are good for beginners, and they are much cheaper in the long run as each bottle will do 180 tests.
Cycling is hard on fish. The best thing you can do is frequent water changes to keep the ammonia+nitrite levels low. The fish you bought may have been a little weak to begin with, and going through the cycling process did them in. When I picked out my fish at the store their fins were all flared out, super active, seemed very healthy. I went back to the fish store yesterday, and the brothers and sisters of my creamsicle molly were not looking good at all. Quite a few had the shimmies, fins were all clamped, not swimming around. I'm sure if I had bought one of those and put it in an un-cycled tank it wouldn't have lasted long.
Don't get discouraged, I'm sure a lot of people give up when they lose fish at the beginning. Fact is the beginning is the hardest part, once your tank is established things will settle down.