DISCLAIMER: if you happen to be queasy around blood I recommend just reading thank you!

About a week ago I had unprotected sex using the pull out method. I took take action less than a day later but I’m getting weird side effects (?) like some cramping and bleeding. The blood is darker in color than usual and more in clumps. This was a day after my period ended so I’m not sure if it could be old blood or something else. I’m not sure what’s going on or if this is normal. Can this mess with your system like that or could something else be going on?