3. Burning Hair
There are a number of smells which might be an indication of something about to go wrong, especially if you are the only person who can smell them. The brain can actually misfire in some cases and cause you to believe that you are smelling something that is not there, particularly an unpleasant smell such as burning hair. This kind of olfactory hallucination can be a sign of trouble in your brain. One cause that could arise is a brain tumour, while an infection is another. Both of these could easily lead to death if they are not discovered in time, but the survival rate of people with a brain tumour is relatively low either way because of the difficulty of operating on the brain. If you think that you are smelling something which is not there, you should get to the doctor as soon as possible for a check-up.