Questions :)

Okay so I'm new at charting bbt . I have just a regular thermometer (idk if that matters) but I noticed when I would do it orally it would be all over the place (i check twice each morning) and there would be a wide range between them ) then out if curiosity I just would randomly check my temp (didn't chart it if course ) but it would be in the same range . So this morning I checked vaginally and it was still all over the place ?? At first it was like 99.1. And then it was like 98.5 which is a normal temp for me . I don't know what to chart ??  I do get up bec my 8 mo isn't  sleeping through the night yet . But I normally go back to sleep and check when DH is getting up for work ?