Welcome to March and our first tip in the buoyancy series.
For every dive there is an optimum weighting. For a DNF/DYN dive we normally recommend being both neutral overall and pitch neutral (head up/down) at the depth you will be swimming. This is so that you present the smallest possible cross section as you pass through the water. If a diver is not neutral swimming effort will be expended trying to stay down/stay off the pool bottom. If a diver is not pitch neutral they will expend effort trying to keep horizontal. All this effort to stay (down usually) creates extra drag and insidiously changes the diver's stroke as they adapt, swimming muscles accumulating 'memory' of a compromised technique. Many divers correct their buoyancy and then find they keep swimming into the bottom of the pool because they have developed a (compromised) technique to fight the buoyancy that they have been swimming against for months or even years. If this happens to you, trust in the buoyancy check undertaken by kicking off and gliding at your intended swimming depth, get your buoyancy sorted and over time your muscle memory will correct.