Bleeding and cramping

Ok I'm 11wks5d pregnant. I woke up early this morning with red blood when I wiped and in the toilet, with cramping. This went on for about 20 minutes then stopped. I called the ER they asked if I had sex, I said yes last night. They said stay in bed and if I started bleeding again to come in. My question is, I had anal sex not vaginal sex and yes the blood was from my vagina only. Could that have affected the baby any? I did not tell the ER nurse that