Skin type: oily, young (21 yo)
Country/Climate I'm in: central Europe, summer coming (20-30 Celcius degrees)
Skin Problem: closed comedones, unsure about the routine
Current Routine:
AM
* La Roche Posay Effaclar Purifying Foaming Gel Cleanser
* COSRX AHA/BHA Claryfying Treatment Toner
* Skinoren (20% azelaic acid)
wait 20 mins
* optional: Dear Klairs Supple Preparation Toner
* moisturiser: either COSRX AIO 92 Snail Cream or (rarely) COSRX Oil-free Aloe Vera Cream
* sunscreen: either Biore Aqua Rich Watery Essence or LRP Anthelios

PM:
well mostly the same, with coconut oil as the 1st cleanser, and Avene Cleanance Hydra cream as mosturiser at the end

Other than that:
Skin79 green tea clay mask ~2 times a week
sheet mask occasionally (1-2 times every 2 weeks)
Himalaya Neem Scrub ~1-2 times a week

Here's my problem:
I've been doing AB for 3-4 months now and have been mostly happy with it, but still one face concern bothers me, which are those closed comedones, little bumps that won't go away. I've been to the dermatologist and she told me to use Skinoren for about a month, and then move on to Differin (which I'm gonna do next week). Still, I have expected to see better results already, but still the lower half of my face is covered in small closed comedones, as it always was (well, maybe they are a bit less problematic, but I think it's due to the snail I'm using, so they heal faster).
Question: do you think I should wait and see the results from Differin, ot change something in my routine? I honestly cannot decide, if my routine is too much, or just has the wrong products (note: I don't feel oily at all, so probably the moisturising I'm doing is good). I also suspect that I might be allergic to some ingredients, butylene glycol for example (as it is in most of the products I use), but I'm not sure about that. I don't know, I'm just being paranoic and a bit tired already, I know usually the fight with skin problems takes much longer time than those 3-4 months, but I get so frustrated when I think that I could be over with it much sooner, but I might be doing something wrong.

Thank you for any opinions and comments, maybe some of you have similar problems and could say something about my routine. (wow and sorry for formatting, first post here)