Unfortunately, The HPS bulb you've acquired needs a ballast. If you are going with the rubbermaid idea, check out some examples around the forum. I'd recommend using CFL's in the space you have, especially if you don't have a fan to reduce heat. CFL's are cheap and perfect for what your trying to achieve. Get a couple 100watt equivalent bulbs.

Start off by starting over from scratch. You have 5+ seedlings in one small pot (Save yourself a ton of trouble down the road and trash em). Place one germinated seed into a small dixie cup to start. Transplant 3 times. Once from dixie cup to larger 18oz party cup and the third time into it's final resting place - a 3-4 gallon pot.

Your plants will not survive long without proper ventilation so check out how to use a fan for an exhaust and create a passive intake.

I am no expert. But this is a little information I'm tossing over to you before I crash into bed. Maybe enough to get you started... I'd like to see you around and I wish you luck on your first grow.

__________________
"We had two bags of grass, seventy-five pellets of mescaline, five sheets of high-powered blotter acid, a salt shaker half full of cocaine and a whole galaxy of multicolored uppers, downers, screamers, laughers....Also a quart of tequila, a quart of run, a case of Budweiser, a pint of raw ether, and two dozen amyls....But the only thing that worried me was the ether. There is nothing in the world more helpess and irresponsible than a man in the depths of an ether binge...."