Some seeds take a bit longer to get going and no doubt in a week you will wonder why you were concerned.
Do not cover the seedling with anything/humidity dome type of structure, the roots and the plant NEED good air exchange to grow properly and cannabis does NOT need high humidity levels ever, it is not a rain forest plant and is one of the biggest mistakes I see in Grow Diaries.
Only clones/cuttings need high humidity, and only at first when they don't have any roots.
Most cannabis Indica comes from Afghanistan, Pakistan, Morocco etc (the Middle East), areas with very dry conditions.
Most Sativa strains come from low land equatorial regions and grow in the dry season, when it is very dry and not tropical at all.
Hope this helps,..........
Organoman.