Same five products for two years and my skin turned on them in October

Buy a cheap hygrometer before you buy any skincare. Mine sat at 28 percent relative humidity in a flat with modern radiators, and that alone was enough to turn a routine that had worked for two winters into a flaking mess. A small humidifier in the bedroom overnight got me back to the low forties and my skin was recognisable again inside about ten days. That is a fifteen quid diagnostic against a fifty quid guess at a new moisturiser.

I would look at the retinoid before the humidity. Two nights a week in July is not two nights a week in October, because your skin is already drier and the same dose lands harder. I drop from three nights to two and switch to applying it over a moisturiser through winter, and that alone stops the seasonal flaking for me without touching anything else in the lineup.

Flaking and tightness I would happily experiment with. New closed bumps in a specific area that were never there before, persisting for weeks, I would get looked at rather than guessed at, because that pattern has several causes and only one of them is your moisturiser. A single dermatology appointment is cheaper than six months of swapping products.

The mistake I made in exactly this situation was changing four things in one week, feeling better, and having no idea why. Take one product out, wait two weeks, put it back, wait two weeks. It is agonisingly slow and it is the only way I have ever actually identified a culprit. I wasted about four months and two full sized products the year I tried to do it fast.

Different flat can mean different water. I moved 40 miles into a hard water area and my cleanser stopped rinsing the way it used to, which showed up as exactly the tight, flaky feeling you are describing. A shower filter did not fix it entirely but a change to a non foaming cleanser did.