Black poop , blood

Hello ladies

My baby girl is 3 months old, this morning when I walked up to her she had blood around her right side neck and I didn’t know exactly where it came from . Her mouth was clean , checked everything was clean. Later on in the evening her stool was black .

You know when you google something it’s always negative.

So my conclusion is she probably was spitting blood this morning.

I’ve been eating smoothies and spinach could that be the cause , her doctor is out of town for 3 weeks, Should i go to ER .. or wait another day. ??