If I may say in general:
In difficult situations, for example if you get COVID-19, you should be as sober as possible so that you have a good self-awareness. Because of my previous illness I have a little "pulse oximeter" at home. Doesn't cost very much and can be used to measure the oxygen saturation. This can be very helpful in deciding if and when to call an ambulance.
You should also know that if the lungs are heavy attacked and breathing continues to worsen, it can happen very suddenly and quickly. In such cases it is possible that you can become helpless or paralyzed. Especially if somebody live alone with COVID and symptoms, he or she should therefore prepare a little. For example, by having the cell phone always within reach and a speed dial set up for emergencies. It also makes sense to have a list of important dates, your health insurance, a list of your personal medication and an emergeny contact of kin ready.
Please note: These are only personal experiences! - But I'm not a doctor. This is and is not intended to be medical advice and cannot replace a doctor's visit or professional help!
Be careful and stay healthy.