Is this a miscarriage? :(

Em

So last night I had pain in my left inner elbow, lower/upper arm and hand and it hurt all night and still does. I took a pregnancy test this morning and it said “not pregnant” could this be diluted since I drank a bunch of water towards the end of the day yesterday? I went to the ER a couple of days ago due to bleeding and my HCG levels were at 10. They did an ultrasound and they found a cyst on my left ovary. I have an appointment with the OBGYN in the morning.