Growing Vegetables Inside - pests

I took five cuttings from an heirloom brandywine tomato in
November. Stuck them in some media and soon had roots and then shoots.

About January I first noticed some tiny insects about 1.5mm long at
most. I have never seen any plump ones nor have I seen any webs.

Cuttings being in three inch pots it was easy to wash them off with the kitchen sink spray.

Then the frequency and number of insects increased and I bought some Neem Oil Extract Amazon and used it as directed.

Now my plants are overwhelmed. It is like I offered a free lunch or opened a soup kitchen for tiny insects.

What happened?