Your light is fine. I was just making sure it wasn't an old mercury vapor light, which put-out more heat than usable lumens.

Assassinating your plants now is up to you. But I always recommend one take their plants as far as possible, since success and failure can both be a learning experience, and if they're still alive, they may pull through and be the best thing you've ever smoked.

It'll be up to you to find a happy balance of waterings and feedings though. Every growroom is different, as are the strains, the tapwater, the nutrients, additives, lights/distances/lumens, heat/cold/humidity...but as you read through the growlogs, you will start to see what other's are doing, when they are doing it and why they are doing it. Find a successful growlog, and ask questions if confused.

Try to keep it simple though. Don't go out and buy hundreds of dollars worth of additives, until you learn how to use the basics. Usually you'll find the additives are 'snake oil' crap anyway.