Ay alam ko yan, nangyari na rin sa akin especially pag stressed ako or pag sobrang dry ang balat ko! Those tiny red/purple dots are usually petechiae, basically small blood vessels na nag-burst under the skin from scratching, kaya mukhang dugo talaga pero hindi seryoso. Since you're experiencing this regularly though, mas maganda siguro i-check with your dermatologist para ma-rule out kung may iba pang cause, and they can also recommend how to manage the itching so hindi ka na mag-scratch ng ganyan. In the meantime, try moisturizing agad after shower and keep your nails trimmed to minimize damage pag kinakati mo ang balat!