Plan B side effects or implantation bleeding?!?

It's probably too soon for implantation bleeding, & it's common to get bleeding from the Plan B around this time.
It's just a case of waiting until you can do a pregnancy test. I suggest doing one, even if you get some bleeding.

Plan B is not as effective as regular hormonal birth control. It's simply worth a try in an emergency. If you're already ovulating then it may not be able to help you, & in that situation I suggest women go for the other emergency pill called Ella (Ulipristal Acetate), as it's proven to work in more ways.

Plan B works by delaying your ovulation until the sperm leaves your body. If you're already ovulating then it can't do that. Some think Plan B works in other ways, but the Manufacturer does not claim that. They say it's possible, but don't say it does, as it has not been proven.

You can probably work out if you're at high risk from pregnancy, from that.

It's common to get irregular bleeding & any hormonal symptoms that you'd get with a period or pregnancy, for example. Some women find their period is late by weeks or months, or that their bleeding is irregular for months afterwards. Others don't notice much of a change in their menstrual cycle.