sleepiness too much O2?

[gsaikin]

I have NSIP (non-specific interstitial pneumonitis, fibrosing) and MDS (myelodysplastic syndromes - which make me anemic - hgb hovers around 9.5 to 10).  Over the last few days, my O2 sat has hovered around 85-89, with heartrates upwards of 120.  My sugars (I'm also diabetic thanks to Prednisone) have also been on the high side (sometimes this means an upcoming infection, pneumonia, virus, etc.).  Since this has been happening with just getting up to go into the kitchen, or go to the bathroom, etc., I was told by my pulmo to up my o2 to 5 liters (from 4).  I did, and have noticed extreme sleepiness - which if I've read right, can mean too much o2!  I will be in contact with my pulmo, of course, if this stays, or gets worse...however, it looks like  a catch-22.  Increase the O2 to perfuse my body better, and get too much O2, or leave it at 4 liters, and deal with spo2's in the 80's...which is more dangerous?  My guess is the combination of MDS and NSIP is making this worse.  I am anemic, and what little o2 I do get in, I don't have enough hemoglobin to carry it around!  My DLco is 20% of predicted.  As a matter of fact, all my PFT readings plummeted by 50% or more between 2007 and 2008.  I will be getting a new pft in October of this year.