I am new to gardening and started some tomatoes from seeds about a month ago. Things grew so great and then a few days ago I started seeing tiny brown spots on the larger under leaves. I am worried that they might already have a bad fungus or something. They are organic heirloom plants and this happened the day before I started taking them outdoors to harden them off.

they have been growing under some grow lights- full spectrum. I water around the base with a plant sprayer/mist. they have gotten 14 hrs of light since they emerged and a little fish/kelp mixture a few times.

Can I just pinch off the spotted leaves prior to planting in the ground or is this a really bad sign that they will get a blight or fungal disease later on?

thanks for any and all responses! :)