Brain Fog

TIA. I've been dealing with persistent brain fog and occasional episodes of feeling almost lightheaded/near-blackout for a little over two years, and I'm trying to figure out what else I should discuss with my doctor.

The symptoms are difficult to describe. Most of the time it's a mild, persistent “fog” where I don't feel quite as mentally clear or focused as I normally would. At other times, particularly when I'm in a social situation and start feeling mentally overwhelmed, it can become much stronger. I don't actually lose consciousness, and it's not spinning/vertigo. It's more like my brain gets extremely foggy and I feel almost like I'm getting close to blacking out. Sometimes I'll need to step away or go somewhere quiet for a few minutes until I can focus again.

It seems to happen more often in social situations, although it isn't exclusively related to them. I don't always consciously feel anxious when it happens, although I have had a significant amount of family stress over the last several years. My doctor thinks anxiety may be contributing or the only factor.

I've had fairly extensive blood work, which my doctor said looked normal. This included a CBC, metabolic/chemistry panel, glucose and A1C, thyroid (TSH), iron/TIBC/iron saturation, vitamin B12, vitamin D, testosterone and several other hormone levels. My A1C was 5.2 and my recent glucose was 97. Nothing significant was identified as an explanation for the symptoms. Testosterone levels were a little low on a previous blood work but looks good now

I also tried an elimination diet for about a month without noticing a meaningful difference. I've been exercising regularly for roughly the last 4–5 months, usually around three days per week, and have lost some weight, but the brain fog hasn't noticeably improved.

A few things happened around roughly the time this originally started that may or may not be related at all, but I thought they were worth mentioning:

I moved into a house (2.5 years ago about the time this brain fog started) where mold was found in the crawl space. The landlord said it was cleaned/remediated, although I don't know how thorough it actually was. I eventually moved out about 8–9 months ago.
Around the same general period I developed gastritis/ulcers.
I was prescribed dicyclomine for the GI problems. I believe some of my worst episodes occurred at least at the start during the first week I was taking it. I remember being out getting coffee with friends and becoming extremely foggy/near-blackout and needing to step away somewhere quiet to try to get my head clear. I contacted my doctor and was taken off the medication. The symptoms continued intermittently after stopping it so not sure if this had anything to do with it or not?
Like I said this is about the time I moved into a new house and had a lot of moving stress.

I've wondered about POTS or another blood-pressure/heart-rate issue. I checked my heart rate myself using a fingertip pulse oximeter while lying down and then standing. I believe it increased only around 10-15 beats per minute and then came back down fairly quickly. I occasionally experience skipped heartbeats, sometimes more frequently, but they don't seem to occur at the same time as the brain-fog episodes.

No sure if it could be parasites or sleep may be a factor? I generally try to get 7.5–8.5 hours, although some nights are less than 7. I don't know whether I snore or have episodes of sleeping trouble.

My main question is: What other causes or evaluations would be reasonable to discuss with my doctor before assuming this is entirely anxiety-related or are there any?

I'm open to anxiety being part or all of the explanation, especially because social situations seem to make it worse, but I'd like to make sure I'm not overlooking something else as I would love to not be on anything for anxiety but still want to feel well. If you guys have any thoughts on this and what to ask the family DR? I probably forgot something. But thank you all