Iris flowers like these only last a couple of weeks at the most so this is fairly normal.
Generally speaking dead heading is good for bulbs as the plant then concentrates its energy on the bulb for next season. However, the Irises in your picture are very difficult to get to repeat flower in subsequent seasons. The bulbs break up into tiny ones and take a while to reach flowering size again.

O.K, thanks Owdboggy

I wouldn't go along with you completely there, Owdboggy. The length of time that these type of iris flower can be affected by the temperature. Our potted irises in an unheated greenhouse last much more than a couple of weeks and the ones in the garden longer still. If Alex's iris are in a warm part of the house then they may only last for two weeks.
Unless you are collecting seed, Alex, then dead heading is beneficial to give more energy to the bulb and reduce the chance of botrytus as the flower rots off.
The only reticulate iris that I have found to break down into small bulblets is Iris danfordiae. All the others bulk up well and keep flowering every year.

They may well do so for you B, but for us they last one season and disappear. The only ones which survive, but do not increase are the I Kathryn H, Frank Elder and Ann Germaney ones.
I have tried planting I reticulata ones deeply, in pots, in all sorts of different places and the only ones to return the following year were a few in a deep tub and they got fewer and fewer in number. In fact we no longer bother with them as we reckon they are a waste of money.

Interesting, Ob, we have no problem at all. Even bulbs that are left on the surface grow and we regularly have to divide clumps of bulbs as they become crowded.

Horses for courses?

I agree with Owboggy I rarley see Recticulata a second year,Still i bought some from Scotland last year thought that should sort it ,but in containers and pots there is 10/15% have not come up at all.Oh Dear !!!

I suppose it is best to remove the faded blooms, and just wait and see what happens next year.

Plus, to clear up where these irises are. They are outside on the windowsill.
The advice from the tag was to keep them in the pot and transfer them when dormant. So they are still in their original pot with a small green ceramic one disguising it.

This is interesting, because they rarely last more than a week, here, and are more likely to fade after three days, when forced like that. Even in the ground each individual bloom rarely lasts more than 3 days. The same happens with Dutch and Bearded Iris, though at least Bearded Iris opens more than one or two blooms from each spike.