What is this plant? In pain!?

According to your description, it seems to be Fever Nettle. It is a shrub with inconspicuous white or greenish blossoms and leaves are covered with stinging hairs. Its stinging hairs has a strong mechanical chemical reaction which can occur burning sensation or itching to our skin later skin gets reddening and often blistering. Even sleeplessness and fever can occur when large areas of skin gets affected. Bath affected skin areas with soap solution and apply Corticosteroid ointment.