It's pretty normal to feel a little nervous and stressed before a test. Just about everyone does. And a touch of nervous anticipation can actually help you get revved and keep you at peak performance while you're taking the test. But for some people, this normal anxiety is more intense. People who worry a lot or who are perfectionists are more likely to have trouble with test anxiety. Students who aren't prepared for tests but who care about doing well are also likely to experience test anxiety. If you know you're not prepared, it's a no-brainer to realize that you'll be worried about doing poorly. People can feel unprepared for tests for several reasons: They may not have studied enough, they may find the material difficult, or perhaps they feel tired because didn't get enough sleep the night before.
If you find yourself thinking negative thoughts ("I'm never any good at taking tests" or "It's going to be terrible if I do badly on this test"), replace them with positive messages. Not unrealistic positive messages, of course, but ones that are practical and true, such as "I've studied hard and I know the material, so I'm ready to do the best I can."
Breathe deeply and slowly in and out through your nose. And have everything you need: scratch paper if permitted, calculator with fresh batteries, pencils, erasers. Water if permitted.