i would suggest taking a sick day! if you're having such strong detox symptoms, then your body needs rest. a lot of people need to do their fasting during time off, or they specifically take a few weeks off work just in case. it is sooo important to be able to focus on nothing but getting well. my fast has caused me tremendous weakness and fatigue. there's NO WAY i'd be able to work right now. some people can manage it, and they function just fine or even better while fasting. but for a lot of other people, that's just not the case.
you mentioned previously that you sometimes take time off work for a work-out session... look at it like that: take time off work to rest so that your fasting body can do a "work-out" detox session :)