Wake up early but my bbt is still higher

Shauna • TTC after 2 miscarriages & with PCOS💗

These past 2 days I have woken up 1.5 hrs earlier and 2 hrs earlier. But when I take my bbt as soon as I wake up well yesterday it went up by .1 degree and today it was up by .21 degrees. Are those invalid temps? I had a full nights sleep and I took them literally after wakin up.