If you had protected sex, and he ejaculated outside of you, it doesn't sound like there was a reason to take the "morning after" pill. As you experienced, that pill comes with many side effects and it's best to avoid it if possible.
If you're having sex and are concerned about pregnancy, it's best to look into different methods of birth control and not put your body (and worried mind) through the extremes of an emergency contraceptive if unnecessary. To answer your question-- no, there's nothing to be worried about.
Learning more about sex can help you better understand how to stay protected and worry-free, if you are ready.
Here are some resources to help:
And about emergency contraception:
Hope this helps.