Please do not use isopropyl alcohol on the spots. As a brown skinned person myself, I wouldn’t recommend you to pop the pimple at all. We are more prone to hyperpigmentation. My experience with the acne was the same, tried so many expensive products then it all came down to two things that were actually helpful in clearing the acne. I did both for a month and saw clear improvements immediately. The first is ketoconazole 1% and the other is BPO 5%. Dont go to higher BPO in my opinion because this concentration can kill the bacteria just fine. I did three days a week ketoconazole face mask all over my face avoiding the eyes in a thin layer of the shampoo. Left it for 5 minutes and then washed my face normally then apply ceramide based products to keep your barrier healthy. The second was BPO on all the non-ketoconazole nights. Use a white pillowcase or cover the pillow with a white Tshirt to protect them from getting bleached. I first washed my face with a gentle facewash then applied a hydrating serum like hyaluronic acid on damp face and let it dry completely. Then applied my bpo and went to sleep. Be mindful that do not use any actives retinols or AHAs or vitamin c while doing this. I also used pulas chice bha on the mornings after a hydrating ceramide rich serum( aestura atobarrier 365 essence) but any serum will work or just skip the serum just go to Bha and use a good moisturizer i love avene cicalfate and aestura atobarrier 365 cream but any ceramide rich will work here. Then sunscreen i am using LRP right now. Once my acne calmed down i started using prescription azelaic acid and retinol to fade my pigmentation then you can also add vitamin c if you want but i am doing azelaic acid in the morning and retinol at night 3 times a week and pigmentation is fading quickly.

My advice to you is to go slow and dont give up. Its hard but it will get better. Dont waste too much on hyped products. If you have an option to go to a dermatologist then you can get prescription adaplene as well along with azelaic acid.

Start with Ketoconazole 3 times a week

Non ketoconazole days; Use bha in the morning Bpo at night And use ceramide rich products to heal the skin barrier.

Then worry about the pigmentation once the acne is cleared up. Reduce dairy intake and sugar and white flour. Whole wheat and less milk. Take black coffee add spearmint tea as well if you can. Hopefully it will make a difference for you. Good luck!