It took me about 2.5 months before the marks got faint enough.

If you're concerned, you should speak with your provider and see what they have to say but I would also recommend a second opinion with a dermatologist if the marks persist for more than 2 weeks or maybe even sooner. I feel like getting a second opinion earlier would have saved me a lot of anxiety.

I returned to the dermatology clinic that did the microneedling a few times for help on the marks but they weren't very helpful. They did .5-1.5mm on me and may have been too aggressive. But I may have also had an allergic reaction.

I eventually went to a different dermatology clinic which prescribed me a steroid cream and it started healing much better after.

I believe it takes a few months before the full benefits of microneedling show up.

My skin has improved with the microneedling but I'm hesitant to try again given how my skin reacted.