What you experience is pretty normal.
You took the "short track" and aimed for a really small board, as your first board (thats okay, it just has its costs....)
Many of us, learning on bigger boards, have found the same difficulties when going small.
Just in a "pleasant" rate, as we have simply downsized slowly while we progress, so only going smaller when we could feel the board was too big.
You jumped straight to the goal - weight equal volume as most use when experienced, so of course you will suffer dramatically when learning.
I dont see any recommendations besides practice practice practice - OR, borrow/get a bigger board and you will learn superfast.
Peter