Just keep your cool man.
There isn't much, you can probably do.
I'd dry it right out until the pot feels light.
Do you know the ph of your soil?
Lumens aren't an accurate measurement to go by either. As far as I'm aware lumens is how bright the light appears to our eyes.
Plants feed on PAR (photosynthetically active radiation).
You would probably be using more electricity, and have way less PAR than a 250watt hps. Even a 150.
With the information you'be provided, I think dry it out. Cross your fingers. Maybe get a low wattage hps. Believe it or not, itd probably run cooler too.
Work on proper air extraction too.
I know the feeling man. You obviously love this plant as much as I do. They're like our children. It hurts to lose them.
But losing a plant is just a learning curve.
I think don't give up. Try to save it. Then at least if it dies, you'll have a good idea, what to avoid next time.