Bleeding after Plan B?

So, I took plan b before going to bed because I didn't use a condom during sex. The next night I woke up feeling naseus. Which is normal, according to the box. That feeling came back a few times through out the day. And NOW.. I woke up this morning bleeding and feeling like I started my period.... I just finished my period LAST WEEK.. I read what some side effects might be and spotting nor bleeding are on the list. I feel like I'm doing more than just spotting. I've tried calling my local planned parenthood and they said to call the number on the box. That was no help because they were closed. What do I do? Should I be concerned? I need Help!!