Perfectly understand your reluctance to visit a doc in person.
Might I suggest an Online Consultation on this App with a Dermatologist of your choice?
Your problem suggests to me (from your description) that or may not be a simple fungal infection but something we allude to as Seborrheic Dermatitis and Striae Dystensiae (stretch marks for the lay-person)
Stress and dry skin will most probably be factors if my intuition is spot on.
Next Steps
Consult me or any Dermat Online
Health Tips
Moisturize with any moisturizer at your disposal and wear loose fitting clothing and remain in a cool ambient environment.