The only issue is that you might end up ejaculating on your face so try to be in control and flip in time and do try it out.
It is often presumed that masturbation for men is very basic and there are only one or two positions when they can pleasure themselves.
If you can then you are in for a very interesting and fun, solo time.
It can be a bit hard to do if you are not fit and flexible so try at your own risk.