As you can imagine, pre-med is quite challenging. In a sense though, it is no different than the other majors. That is, as challenging as it may be, with dedication and hard work, it can be very enjoyable.
I think it is much easier if you love what you are doing, so the end point (medical doctor) is one thing, but if you can make the process enjoyable you would be way ahead of the game. It is also much easier the more you know abut the process, so keep asking these questions to as many people as you can and get as much of a feel for the process as you can.
Hope this helps.