@erichu I'm eager to give you some good news. I had COVID in August and after a few months my hair started coming out much like yours. My hairdresser and dermatologist both recommended taking 10,000 mg of biotin a day. It worked. Before long my hair stopped falling out and started growing back.
Biotin is availabile OTC as tablets or gummies. As a bonus, my fingernails are longer and stronger too. Good luck and assuming there's no other medical reason, don't worry.