Is she done for?

Thanks for the help!

every other irrigation can still be too much. Stop fertilizing completely for now... Those symptoms aren't new, so try to think back to how it started, how it looked and remember to ease off before it progresses next time. All any of us can do. Your fox farm soil is "hot" soil. It is good for upto 8 weeks with no fertilizer needed (usually less). Less as you add more perlite and other stuff on top of typically less than 8 weeks. Seeds are packed for the first 2 weeks or so. If you've been feeding lightly from the beginning in this context, it is still too much. No big deal... bet, she can recover. Is the heater blowing hot air on it? Definitely something to avoid, and you'd know by placing your hand at the plant if it is elevated enough. But, burned tips and such - nutes related given your contexts. In addition to raising the heater, you can angle it -- safely or not? those tings are dangerous, so don't do anything crazy with it. Some have tip sensors too. So, I'd give a good irrigation with exra runoff and wait until top 1" is dry and do it again. Of course, read the plant... keep doing this until new growth stops twisting at the least. go from there.

Also most nute feeding charts that come with them are pretty strong.. I started my girls at 1/3 str and i'll ramp them up slowly if i don't see issues..

Are you using Fox Farm Ocean Forest? If so It has enough nutes in it for 3-4 weeks of growth, maybe even a bit longer.