When the inflammation doesn't go down with an injection!

Hello. I have acne-prone skin, and since my skin is on the fairer side, I tend to get marks easily. So, whenever possible, I try to visit a dermatologist as soon as a breakout appears to get an anti-inflammatory injection. However, depending on the type of blemish, there are some that don't subside immediately even after the injection. The red pimple I took a picture of is one such case. In this situation, is it better to get another anti-inflammatory injection, or is it better to try to soothe it at home? I am curious about the best way to get rid of it cleanly without leaving marks.

Also, what is the best way to handle acne that feels a bit soft inside? For the hard ones, I can go to a dermatologist to get an anti-inflammatory injection and extraction, but is it the same for the soft ones?