From PC/Beautypedia:
Dehydrated Skin vs. Dry Skin
Having classically dry skin is easy to recognize. Dry skin frequently feels tight and dry, with no oil anywhere to be seen. This situation rarely fluctuates; skin feels dry all year long. The dryness might get worse depending on the climate, season, or activity, but regardless of those things, without great skincare products, the uncomfortable dry, tight feeling will persist.
Combination skin is when you have areas that are oily, usually in the T-zone (nose, chin, and center of the forehead) while skin on the sides of the face or cheek area is dry.
On the other hand, dehydrated skin can look and feel like dry skin all over your face but there’s a major difference: Dehydrated skin tends to come and go, it does not persist.
Another hallmark of dehydrated skin is that it’s often accompanied by a more than normal or even excessive amount of oil on skin’s surface. Despite this excess oil flowing through the pores all over the face, skin still feels tight or dry everywhere on your face, and these signs are often accompanied by flaking. Very frustrating, but you knew that, right?
Simply described, if you feel your skin is dry underneath under an oily layer on top, most likely you have dehydrated skin. Surprising fact: For many people, the skincare products they’re using might be to blame!
How the Wrong Products Can Cause Dehydrated Skin
Although dehydrated skin can be caused by different factors, more often than not it's the result of using skincare products that contain harsh or skin-sensitizing ingredients. It can also develop from using the wrong products for your skin, which leads to an imbalance. In essence, dehydration can be viewed as your skin complaining that it doesn’t like something you’re doing to it.
Skin-aggravating ingredients like SD or denatured alcohol, menthol, peppermint, or fragrances (synthetic or natural) can dry out the surface of skin and leave it feeling dehydrated. It will also stimulate excess oil production at the base of the pore, so skin ends up being oilier and more likely to get clogged pores.
The same can happen when you use abrasive scrubs or stiff-bristled cleansing brushes. All of these are the consequence of damaging skin’s surface—an undisturbed skin surface is exceedingly important to healthy-looking skin.
Using the wrong combination of products or using certain products too frequently can make a mess of things. For example, even though an AHA or BHA exfoliant, high-strength vitamin C product, and a high concentration of retinol can have amazing benefits, for this skin type, using them every day can result in a dehydrated look and feel with excess oil sitting on top of it.
This is a highly individual response, so it's important to pay close attention to how your skin responds to more potent, effective products such as these. Based on how your skin responds, adjust usage to get ideal results. For these types of products, once- or twice-daily use isn’t mandatory to see improvement. It’s a balancing act and your goal is to not tip the scale in favor of aggravating skin.
The PC 2% are non-silicone based, so is the CosRx BHA (which is a gentler form but ime not as effective, though works well for plenty of people). I think if you're tolerating the 1% well you can probably try the 2% liquid. Think I suggested the 1% first to ease in to it since you were so sensitive/compromised to gauge the reaction?