Trying to apply a lot of effort and straining to do things can push you to learn poor movements.
Your body will find the most efficient way of doing something with what it has right now, not necessarily accounting for what could be built if you worked in a particular way. Straining to lift heavier at the cost of form means your numbers go up, but are you after numbers? Or changes in your body?
Take it easy.
Especially when you’re learning new movements, apply a little less effort and keep your focus at about 60-70% of total available.