I have the same symptoms
Pepper - TS Moruga Red
Substrat - compost + coco
Light - Fluorescent Lamp 120w
Water - 6.5 pH
Treatment - Spray one time Bacillus Subtilis, Spray one time VALAGRO: Kendal, Megafol, MC Start
These are my assumptions.
There is very little information. It is difficult to judge only by appearance.
Pepper pH is ideal 6.5 - 6.8 pH 7 can cause deficiencies.
The cause can be a combination of many problems.
I suggest drying the root system. This can eliminate some problems.
1.The pepper plant doesn't like over-watering and you left it out in the rain.
2.pH 7 on the verge of alkaline environment.
3. Perhaps there is a lot of phosphorus in the fish emulsion, and it is toxic.
My recommendation is to stop watering it until the turgor is weakened.
Habanero Maya Red.
This plant is about 3 years old.
Treated with antifungal drugs.
Help identify the disease.
Symptoms
New leaves have become very small
New leaves are deformed
First of all, dry the substrate until the turgor falls. Do not water often.
As the brother wrote above, measure the pH and PPM of your water when irrigating.
Change the substratum - this is a fundamental decision on which there is time to think.