The time to relax is when you don't have time for it. 

Are you worrying about everything every minute of your life? Will I score well in my exams? Will I get a good college? Will my boss give me my bonus this year? Can I afford this exquisite china? 

Yes it's normal. The devil haunting your soul is Stress. I was over with my board examinations 10 days ago and honestly even if they're over , the stress that haunted me isn't. I still wake up in the middle of the night with my sub-conscious mind telling me to study for my economics board ( not that it didn't go well) but anyway you get the point. Even if you manage to convince yourself that you're stress free , your mind will always have other plans for you. And it's not just students , it's everyone; from every walk of life. Your mother stresses about making your food in the morning, if she doesn't get up on time , everyone will be late. Your father worries about financial constraints or where you barged off with your friends without telling him ( not an ideal situation, believe me) .
So basically , everyone has something to stress about. But it's not what you think about , it's how you overcome it. For some people it's music , for some writing or dancing. Stress is a deadly virus which can only be secreted by the activity of your choice. Don't think of it as a burden , more of a challenge. Challenge yourself to be free of the unnecessary shackles you have tied yourself to. Why stress about your result when you have no control of whatever it is? Why stress about your children or husband getting late , it's just a time , it's just a temporary situation; everyone will get over it.

 Stress demands to be outwitted. Take it all out. Listen to music, write it all out , dance your worries away ,read to escape reality, play your favorite sport BUT don't keep it in. Never keep it in. Mental stress can result in physical destruction of your body which is not desirable. So take it out. Remember that this too shall pass. The situation you are in today will not be there next week or next year. It's temporary. Everything that happens to you is for a reason and for a specific time period. You do not need to drag yourself to melancholy for a thing which will be over before you spell out mississippi ( see I can make humor with sarcasm).

So chill out and be yourself because your mind is yours. Tame it , endure it and learn to enjoy it.