You've dumped them in chlorinated water, possibly containing chloramine also, with no established bacteria, and without any filter they'll just be sitting in a high concentrate of their own waste, resulting in nitrite and ammonia which will burn their respiratory, eyes, scales, and this will shortern their life span and they'll eventually die, in a few days, weeks, or maybe years if they're hardy enough.
And if you do add a filter now, they'll still have to go through the high levels of ammonia and nitrite involved in cycling a tank, which they may or may not survive, either way it's not very nice for them.
I've done several huge posts about this for new fish keepers in the past, but without search I can't dig them up for you.
But the best thing you can do now is go out and buy a Fluval 1 or 2 internal filter for £10-15 and put it in, keep feeding them as normal and hope they survive the cycle, if they do then you'll just need to change 15% or so of the water every one or two weeks, and treat the water going back in with a product called aqua safe, or leave it to stand for a day or two before you put the water in the tank.
I won't go into too much lengthy detail, but the bacteria cycle is what establishes and keeps alive, the bacteria that eats the nitrite and ammonia and keeps both at zero, both of which are harmful and lethal to your fish.
The resulting waste of the bacteria are called nitrates, these are much much less harmful to your fish, and you can remove these by changing the water every week or two.
