I checked my oil to see if it's milky and it's not

you may have a leaking head gasket at the exhaust part of the manifold and you are burning antifreeze in the exhaust. with the car running put your hand at the tail pipe and see if moisture forms on your hand. you may also want to do a compression check of each cylinder to see if the head gasket is the problem. also there is a chance you may have a leaking water pump. see if there is a water mark on the back side of the pump where there is a small hole. it may leak only during use but will leave a stain on the metal