peat pellets? may have been too acidic.
i'm not a fan of those because of how much water they retain, too. It's too wet for the seed at times. oxygen needs to penetrate. but, many make them work well. i'd soak in large volume of pH-balanced water to ensure they aren't too acidic.
some seeds just won't germinate. usually due to age if they aren't hollow / malformed. I used jiffy pucks my first time and only had a 75% success. i don't do anthing special now and have near 100% success. Keep it simple, is my suggestion. Moisture and darkness is all a seed needs to properly germinate. The darkness is more for the tap root.. if roots are exposed to light they differentiate into stem, which would only confuse it early on.
you'll know better in hindsight as you plant more... try new things..
9-10 days is still possible.. better to leave them unmolested for 14 days to be certain they failed... probably rotting by that point.
just keep them moist before it sprouts and that's all you can do. after that it's safer to let medium dry out a bit before re-irrigating... once it has a root.