Someone will come give you better ideas, but my suggestion is- get a bigger tank. Much easier to cycle/set up.
But if you want to stick with the 5 gal, keep up with your water changes. Do one daily. Add nothing but your Prime. You can add 5 times the labelled amount (which it also says) to detox in an emergency. I went through a whole bunch of that stuff while I was cycling my two tanks. (just recently). I think you can treat your ich easily, but luckily I haven't had to deal with it.
I *think* ich can be treated with salt, but I might be terrifically wrong. However, go back to the petsmart (and actually, if you want, go on to their website and print out the products you plan on buying, they will honor the online price and in some cases it is a big savings), get your airline tubing, and get some ich treatment. Get enough to treat for a while.
Does your whisper filter have activated carbon? I'm pretty sure you have to take that out if it does.
My other suggestion is get Bio Spira. You may not be able to get it at petsmart, is there another fish store around? Search online to see- this stuff is a miracle. It should be in a small foil packet and refrigerated. IF it isn't don't buy it- and don't accept any substitutes (aka, Cycle, Stability, etc- they don't work). But with the Bio Spira and Prime, you can keep the ammonia and nitrites from being toxic while you treat without water changes. I went almost a week without doing a water change (daily checking of my water parameters though) using Bio Spira (I was letting it set itself up in the tank so I wouldn't change it out- same as you won't want to change out the meds).
However, if you can't find the Bio Spira, just simply do a water change and treat the tank afterwards. Do a water change the next day and treat it immediately afterwards. So you'll be changing out, but adding in at the same time.
Did you get a test kit? API Master Test Kit is the best. I'm assuming since you had a sky high ammonia and no nitrites and no nitrates, you haven't cycled yet. Read all you can, that will help.
But I promise, don't give up, it will get better.
And honestly, if you can get yourself a 15 g or larger, it is so much easier. My 55 gal cycled so much quicker than my 10 did, and the larger a tank is it is actually easier to do the waterchanges, and maintenence. Plus, the larger tank size means you can keep more fish.
But don't give up- it is worth it.