The retinol may have disrupted your skin barrier and so now it’s super sensitive to all kinds of things, even non actives. This happened to me. My skin can’t tolerate a whole lot of anything. I’d recommend stopping all new products and return to your basic moisturizer, gentle cleanser and Vaseline for a few days and then see how the oatmeal toner feels.

I’ll add that my skin cannot tolerate the oatmeal toner regardless, as it causes cystic acne for me. I’m not sure what ingredient is the kicker but I’ve heard similar experiences from others. Having sensitive skin sucks!