You don’t mention what kind of BC or wing you are using. Some brands will float you face down if you add too much air.
Most students try to float to high on the surface and the more air they add the more the BC pushes them on their face :(
I use a Back Plate & Wing, my weight pouches are as far back as I can get them and if I use just a little air and arch my back I can float face up.
The wetsuit should not be tight, just snug enough to stop water from flowing thru and yes I’ve had some suits make me fell sick. The only time I ever came close to being seasick was from a 7 mil hood that was too snug around my throat. Now in cold water I wear a 2mil hooded vest with a 3 mil bennie. That keeps the head warm and blocks the water flow down the neck :)