Tom ~
I didn't have this experience and frankly, I would have been slightly alarmed to wake up 'tasting blood' with 'slightly bloody saliva'. I have to echo Denise's suggestion to call your doctor's office to ask why this is happening and if it has any negative consequences. Probably not, but better to know than simply guess.
Post-op, my 'AN side' was sore for months. However, somewhere around 9 months out of surgery, the soreness dissipated and I was able to sleep on my 'AN side' again. Now, almost 4 years post-op, I have no trouble resting my head on the side where my incision was made but that area remains a bit more sensitive than the rest of my skull, although not enough to be a problem. I trust that your incision area will eventually heal to the point where the taste of blood and slightly bloody saliva will no longer be an issue.
Jim