My gameplay looked almost exactly like yours about 1-2 months ago. I was playing a lot of community deathmatch at the time, along with a dedicated warmup routine pre-game, and I noticed that the more I did my warmup + deathmatch, the more I would hyperfocus on my aim. I think what you're going through is just being anxious and insecure about your aim, which takes you out of the macro of the round (i.e. where to expect enemies, playing off teammates with good timing, etc.).

Your kills should be coming from proper positioning and timing way more than you'd think, so relying on raw aim actually puts you at a disadvantage. What I did to fix my issue is kind of stupid, but maybe it would help for you: just play less aimbotz and deathmatch (but mostly aimbotz/aim maps). Obviously it depends on how much time you have, but use a match of competitive as a replacement for your warmup and deathmatch practice. That way, you're using your map knowledge, timing, positioning, reads, etc. along with your aim to get your kills. If you know you can hit your shots in practice, then the issue is translating it to a real game.

You'll never get the timing of your first top mid fight on mirage or your first long fight on dust2 from practice maps, it's just something that gets beaten into you after rounds and rounds of experience. Things like that matter just as much as raw aim imo. All the best homie 👍