18 weeks- found strands of blood..

Last night after taking a walk, I started to have slight cramping. This morning, I was having sharp, intense pains on my right side that went straight through to my back-I went to the bathroom and after wiping, there were strands of red blood in a clear mucousy discharge. I called the dr and they want me to come in later today but I'm just going crazy. I'm 18 weeks pregnant. Have never had a miscarriage or any pregnancy conplications. I have had two healthy previous pregnancies. The bleeding is not heavy and is only there when I wipe. I'm so afraid 😢