I suggest you go to an eye doctor or retinal specialist or emergency room ASAP.
I had similar symptoms and you could be having a retinal detachment or retinal tear which needs to be examined immediately.
My black floaters were caused by a vitreous detachment and it is when the vitreous comes off the retina. Normally it doesn't cause huge problems except for floaters that become less noticeable over time but mine tore the retina twice in my right eye.
I also have it in the other eye but only one eye had the retinal tear.