It is the effect of altitude on those who ascent too rapidly to elevations above 3,000 meters. Early mountain sickness will manifest itself in headache, loss of appetite and sleeplessness. Do not ignore these warnings otherwise more serious symptoms can occur which can even cause death sometimes within a few hours. Being young, strong and fit does not help. Descend to a lower altitude immediately.
Doctors are available there during trekking season.
In fact, a pair of open sandals is more convenient and comfortable while visiting the temples and stupas. In some of the temples, entrance may be prohibited for the non-Hindus. Leather articles are prohibited inside the temple precinct. It is better not to touch offerings or persons when they are on way to shrines. Beef is strictly prohibited among the Hindus.