You have most likely developed either a contact irritant dermatitis or contact allergic dermatitis. You might need prescription medicines depending on the severity of the episode and the severity can be determined only after a physical examination to be able to give you medicines (oral or topical).
Next Steps
Kindly visit an allopathic dermatologist near you as soon as you get time. Before you choose your dermatologist read this please : http://www.skinmatra.com/single-post/2016/07/03/Skin-Troubles-Here-is-WHAT-NOT-TO-DO
Health Tips
Do not try home remedies or Google search the medicine. You might not aggravate it. Avoid use of hot water and antiseptic solutions/ soaps for bathing.