How deep did you plant them?
What kind of soil did they go into?
Usually a good moistening is sufficient when the seeds are planted. If you gave em more then it is possible they rotted. But 3 days is kinda borderline, I start getting concerned about then, but some seeds just take longer. Give em some more time... I've had seeds that I gave up on and tossed and then a couple weeks later have em sprout in the compost bin.
in mix soil tha has allready nutrients and perlite.. i do a mega fault. i deep the seeds 3 cm and more.. :/ i wait a few days is better to power up my lamp from now? or is better to wait from the first leafs?