I took plan b a week ago and i had protected sex. and i feel really tired, sleepy and my whole body aches a week after i took it. whats happening and could i be pregnant? please help. im very scared?

Plan B, when taken within 72 hours of sex is about 95% effective in preventing pregnancy. Your body aches may be due to hormonal imbalance or due to an unrelated condition. You should do a home pregnancy test 3 weeks after the episode of sex for which you took plan B. If the result is negative repeat the test in 4-5 days. Use first morning urine and follow instructions for the test carefully.