What Are The Side Effects Of Emergency Contraceptive Pills?

My girlfriend and I had sex Wednesday the 19th and the condom broke. She thinks she was on her period but her cycle has been very irregular recently due to the fact that she just came off of the birth control shot, so it could have just been irregular bleeding. Anyways, she took plan b about half an hour later and the next day she experiences muscle spasms or cramps in the area around her ovaries and a white discharge. At first I was relieved thinking that this was a sign that the pill had worked but after doing some research I read that these could also be signs or pregnancy. I know it is still too soon to take a test but I am still grasping at straws trying to relieve myself. Are her symptoms side effects of the plan b or could they be pregnancy side effects?