Hi. Thanks for your query and an elucidate history. When something like the problems you faced, so severe like dizziness, headache, pain in stomach and visual disturbances after hair bleaching, you should be rushed to ER to see whether this is caused by beseeching or something unrelated to the bleaching. It may not be directly related to bleaching, I would advise you the following: Ask someone to take to the ER. Get vitals checked and investigations as per the clinical findings. Get antihistamine shot and steroid shot if required, Life-saving measures are the most important to start with . The causes and the treatment can obviously be done with time.