Should I still go to work if I have sever's disease?

It depends? Sever's disease or calcaneal apophysitis is the most common cause of heel pain in the growing athlete and is due to overuse and repetitive microtrauma of growth plates of the calcaneus in the heel. It occurs in children ages 7 to 15, with the majority of patients presenting between 10 and 14 years of age. If you have a lot of pain, i think you should rest it.
See Answer Below. Sever's disease is a process that affects the open growth plate on the heel of children. As i see you are 32, i don't think that this is the most likely diagnosis for you. If you are having heel pain, the most likely sources are plantar fasciitis or achilles insertional tendinitis. Perhaps you should have another evaluation for recommendations.