Is it going to cause stress when I change from 24/0 with CFLs to 18/6 HPS? after a week or so maybe

I've had bean in towel in baggie for nearly five days now, and it still hasn't sprouted..should I expect it to do so shortly, or is it not likely that it's going to sprout? Seeds are fresh..too many more days without this one doing anything though and my plants are going to be a bit further apart than I would like them to be..especially if this one's a dud and I have to wait another couple of days to get one to pop.

Thanks, Tom for input.

Godbud, I feel comfortable having light within 8-10 inches...can't feel heat on hand from that far away. Something that is going to concern me..is it easy to have light that is too intense for a small seedling?