BBT measuring...

I bought a digital thermometer last week and started adding to the app my temps. I keep it by my bed and put in under my tongue as soon as I wake as per instructions I've read. Fertile days are given as 10-16th Jan but does my recorded temps (see pic) look they they're doing what they're supposed to?! I would have thought they would have started rising by now?  I don't know whether I've bought a dud thermometer as it was cheap! I also bought the CBFM to cover more ground and that is saying high fertility for past two days now... but I guess if my temp does not rise at all then I may be producing the LH surge but not releasing an egg? ​