Picture a sponge. You want the soil to be damp just like a wrung out kitchen sponge. Not too wet nor too dry.
Yes, overwatering can rot seeds and can lead to soil bourne disease. Also, soil temp, soil type and seed depth plays a factor. A sterile, light, airy, soiless mix works best.
Is the soil surface drying out to the point that you need to water everyday? Perhaps you need to cover it in the future to help retain some moisture, not now of course if its too wet. What are you using for a mix?
I find a fine peat/vermiculite starting medium is best for my setup. I use a styrofoam seed starting kit that I bought at least ten years ago. It holds one flat over a 15 watt light bulb that provides bottom heat and included a transparent lid. Works like a charm and cheap to.
You must be running on the cool side because lettuce is normally up in two-three days. I've had tomatoes pop through in 60 hours or less.
You'll get the hang of it. Just hang in there.
Wishing you the best of luck.