Did you intentionally do something to the image to obtain that effect? Do you see the same color on other images taken at the same concert?
If you only see that weird color on this one particular image from that event, and all the others look relatively normal (ie, except for stage lighting colors), my guess is that it's was caused by what is known as "JPG bit rot". This happens when even just a single bit is flipped in a JPG file. The most common cause of this is a single bit level error made when transferring files from your camera to your computer, but it also is a relatively common occurrence in old hard drives that are failing.
If you are not familiar with this phenomena, a guy put together a fun website that allows people explore the variety of looks one can get from JPG bit rot: http://snorpey.github.io/jpg-glitch/
Attached below is a screen grab from that site where I played around with the parameters until I got a magenta cast over a significant part of the image. If the corrupted bit had occurred earlier in the file, more of the image would have the strange colors.
Please give us more info about the circumstances related to this image.
All my pictures are perfectly normal, some are even perfect
This is a combination of the lighting and the smoke I guess, so I'm not sure something can be done (unless I isolate the drummer and work from there) I have enough photo's of the band, that's not the problem, I was only surprised darkening didn't work as I wanted it to.
FYI here's a normal one
and, o yes, the drummer IS a man AND a classically trained guitarplayer.