If you are worried, a qualified medical practitioner is always more reliable than a web forum.

Insufficient or poor quality sleep can cause problems with attention and memory, and can exacerbate existing conditions.

Poor sleep could be caused by a medical condition (sleep apnoea), or psychological (stress). Often stress can be hard to identify, particularly if it’s long term stress.

Again, this might not be your problem, and finding the right doctor who actually listens to you is important. Don’t be afraid to try more than 1 doctor if the first makes you uncomfortable.