What causes large pimples?

I wouldnt really mind it if i was getting small size easyily popable pimples but lately i havent. I have been getting large size big red non popable pimples on my chin forehead and eyebrows. It is extremely noticeable and causes a lot of pain. I went to my doctor and he said there is no need for accutane. Im pissed though cause these pimples im getting are taking weeks to heal and i look like a bozo. How i make the size of large pimples smaller. Im already on a strong treatment regiment so im just praying for a miracle. Any secrets (no need for medications)