Its started off dark maroon color now its lighter & really gooey a lot of goo.
Happened 3 times already
It could be from the cervix thinning and dilating. Sometimes as your body begins to prepare the cervix for labor it can burst capillaries which is why you can have discharge which hints of blood. Don't be too worried unless it's bright red blood and lots of it. For now just keep an eye out for contractions in case you go into labor. I had my son at exactly 36wks and he was perfectly fine.
More then likely it was your mucus plug and the nickel size blood was from dilation :) there is no need to go to the hospital unless you fill up a whole pad full of blood
It could be your mucus plug. But just to be sure and on the safe side, you should call your doctor and get checked. Good luck!