After wearing tight panties, my vagina gets irritated. Why?

Loose underwear. Consider wearing loose under-clothing for a few days until the irritation resolves. Use of cotton clothing can be helpful. Baby powder may help with chaffing.
Yes, this can occur. It is recommended to refrain from wearing tight underwear. This can cause moisture buildup and retention of secretions that can lead to infection. Try appropriate fitting cotton underwear to prevent irritation.