Miss Wiggle
Practically perfect in every way
yes safest to do the water changes anyway, the way it goes is this
there's nothing that you have told us that you've done that would have miraculously cycled the tank for you, the process often takes several weeks so is unlikely to have completed without you knowing by now.
in addition to this the cycling process is a supply and demand thing, you grow enough bacteria to deal with the waste you have, so even if the tank had cycled to handle the first load of fish you put in, when you added more it becomes un cycled because you've now got more waste than bacteria who eat the waste.
you've got fish exhibiting symptoms of ammonia poisoning and even if the water tests are not accurate the indication is that there is ammonia in the water.
for now it's safest to assume the worst so you should do daily 50% water changes until you can get a better test kit and accurate readings.
there's nothing that you have told us that you've done that would have miraculously cycled the tank for you, the process often takes several weeks so is unlikely to have completed without you knowing by now.
in addition to this the cycling process is a supply and demand thing, you grow enough bacteria to deal with the waste you have, so even if the tank had cycled to handle the first load of fish you put in, when you added more it becomes un cycled because you've now got more waste than bacteria who eat the waste.
you've got fish exhibiting symptoms of ammonia poisoning and even if the water tests are not accurate the indication is that there is ammonia in the water.
for now it's safest to assume the worst so you should do daily 50% water changes until you can get a better test kit and accurate readings.