I just don't understand my BBT

I just turned 27 years old. My husband is 37 and we have been trying to concieve for 3 months. We've been married just over two years.

I have an autoimmune disorder, celiac disease. I was diagnosed two years ago and finally had a negative biopsy from the stomach and intestines in April. That means after 21 months gluten free that the "hairs" in my intestines have regrown and I am able to absorb vitamins. I have bone density loss from the celiac as well. We started trying to concieve in June. My vitamin levels are finally "normal" but I'm clinging to the lowest average of pretty much everything.

My cycle is always exactly 28 days in length. It's pretty regular. This summer I've been working out 7 days a week. Once school resumes next week (I'm a teacher) I'm hoping to do 4-5 days a week. I only eat vegan gluten free. I've been using the Ava bracelet to track my cycle because I was having a hard time consistently temping. During the summer I work as an in-home behavioral therapist so my schedule varies wildly day to day and even with alarms I was forgetting to orally or vaginally temp at the same time. Whether I temp orally or vaginally or with the Ava (which does skin temp) I never see any patterns in my charts. This picture is of a chart using Ava data which I would have put into glow. After I put in my data today Glow moved my ovulation window. My period should come the 25th because that would be 28 day cycle. I am always 28 days. Now after today's data it is saying that I ovulated a week later that it predicted and that my period will come the 31st.

Maybe I'm just getting paranoid but because I don't see patterns in my bbt that look like the sample ones that they give you so I'm starting to worry that either my health issues are getting in the way or that I have some fertility issue that I don't know about.

Ava bracelet

https://www.avawomen.com/?gclid=EAIaIQobChMI7oq6iuvl1QIVwrrACh34YQANEAAYASAAEgL1afD_BwE

Up until today, my period was predicted to come the 25 and my ovulation window was the 6th through the 12th.