Yes, its normal. Don't worry they will all start ripening soon. Personally I remove any tomato that has any color at all. By doing this I stop any future calamity such as birds, racoons, possums and caterpillarss from taking a bite out of my fruit. The fruit when picked early will ripen indoors exactly the same as on the vine and don't believe anyone who says it doesn't. You can leave a tomato on the vine until it shrivels and falls off but why would you?
I’m only getting black vernissage at the moment and it’s 1-2 a day. I have hundreds of pounds of fruit just waiting to ripen. This is a game we play every year and it’s totally normal.
Some people say to let fruit overripen on the vine if you’re saving seeds. Something about fermentation helping coat the seeds and protect them. I save my seeds by letting them ferment in their own juice for 3 days prior to drying.
Some tomatoes can stay on the vine ripe for a week, others a few days. When they’re soft they’re good to go. They’ll ripen on the counter the same way, just don’t pick until they start their color change to ripen. It can be sped up too if you put them near bananas but I only do that to late season tomatoes that I pick green.