Jumebe

It's been 9 months and a few weeks out. I still get light headed when I stand up from sitting. Lasting just a few second to close to a min. I just hold still and hold on to something to just ground me. I drink as much as told to do, I eat the right things,and take my meds/vit and get enough sleep. I have to wear oxygen when I sleep do to my O2 drops to the mid to low 80s. And I wondering how long does this last. Or am I not doing something right.