I am a person who is prone to overthinking things as well and always think the worst and then end up regretting it later, so I feel your pain.
I still think though you have to speak your peace. Just explain yourself fully when you do. Tell him you understand he is busy, but for him to try put himself in your shoes. If you do it with love, it’s really hard to not respect that. If he doesn’t respect it, which he probably will surprise you and respect it, you have a right to be upset.
Don’t ever diminish your own feelings. That is great thing about feelings. No matter what, they are always right and you are always legit in feeling that way. Some people just need a little more reassurance. I am like you. If he can’t deal with it, someone else will.