I haven't been feeling well for the past two weeks and have been sleeping most of the timeday. I haven't been feeling well for the past two weeks and have been sleeping most of the day.

I hasn't been tested, but I think I had coronavirusCOVID based on my symptoms. I hasn't been tested, but I think I had COVID based on my symptoms.

COVID is more common than corona virus (COVID is more specific while corona virus refers to a group of viruses)

I hasven't been tested, but I think I had coronavirus based on my symptoms. I haven't been tested, but I think I had coronavirus based on my symptoms.

I hasven't been tested, but I think I had coronavirus based on my symptoms. I haven't been tested, but I think I had coronavirus based on my symptoms.

I -> have she, he -> has

I lost about 3 kg, but I regained imy weight as soon as I felt better. I lost about 3 kg, but I regained my weight as soon as I felt better.

Not Good feeling good Not feeling good

You could also say "Not feeling well"

Not Good fFeeling Well Not Feeling Well

Not Good fFeeling ill Feeling ill

Not Good feeling well Not feeling well

I continued to havehad a low-grade fever and fatigue. I had a low-grade fever and fatigue.

In this case, the continuous nature is already implied.

I continued to havehad a low-grade fever and fatigue. I had a low-grade fever and fatigue.