Vaginal temping

So I started temping this cycle...mostly to get in the habit as we're hoping to officially start trying in March.  Bought the bbt, figured out glow, etc etc and below is the result.  All oral temps.  A couple of days ago though someone here mentioned vag temping and it piqued my curiosity.  I picked up a second bbt - same brand and model.  For the last two days I've been experimenting and the results are kinda nuts.  Without fail, my vag temp is a half to full degree higher (or more).  Right now, I just tried both at the same time again (one oral, one vag) and my oral came back at 98.1 and vag at 99.3. Whattttttt.  This morning there was a difference of .9 between the two (I used oral for the chart).  Whoa.  Even more surprising, the vag stays consistent way more frequently then oral.  With vag, my daytime temps don't change but for .1; oral can move up and down ,5 and ,6 in an hour.  Nuts.  (Again, just using daytime for experimenting...know they mean nothing for ttc).