This is a tricky question and a hard one to decide. It could go either way, good or very bad.
We are usually pretty good here in Australia protecting ourselves from getting sunburned but sometimes it happens for all different reasons.
Us, tanners, would recommend only tanning after about 3 weeks if you have a sunburn, to get a tan. That is really the time skin needs to heal. I have tanned many times skin that have gone through a sunburn and most of them were completely fine but a few would just peel away and as a normal peeling from a sunburn , it won't look too pretty and I can't do magic so in the end it will be always your decision.
I can try my best to get your skin even in colour but where there is a burn on he skin it will eventually peel and the spray tan won't stop t so it will peel too and not only that , the tan usually sticks more to dead skin and that is when you see those dark patches when you get a tan, with a sunburn it will be more obvious as the skin is damaged.
You will still need to exfoliate, make sure it is very gentle and please, if you are very badly sunburn just give your skin a break and the only thing that should be going on your skin is Aloe Vera, it soothes and reliefs the skin.
Remember, I am a tanning specialist, not a skin specialist or a Dr so always sick your Dr's advice and always , always wear sunscreen.
Your Personal Tanner