Lower than average BBT?

So I’ve been charting for quite a while (almost a year) and used my charts to avoid a pregnancy. I’ve been TTC for 3 months and so I’ve read more about charting. I noticed that my temperatures fluctuate between 96.4 to 97.7 (35.7 to 36.5 Celsius). I saw that for many many charts that you guys share here your temperatures are between 97 to high 98.

Is this low temperature an issue? I read that average temperatures should be 97 to 97.7 before O and 97.7-99 after O but my temperature never even gets to 98. I can track ovulation, I see the temps getting higher after O but still. I attached last months BBT.

Should I be concerned?

Other info, I notice it’s been a while since I don’t get EWCM like when I was younger.

I appreciate any help.