Retinal detachment/ is this a possibility?

I am 24, 8 months pregnant with my second child. It seems that pregnancy does a number on my vision. During my last pregnancy (2008) I suffered corneal erosion in which took until about a year ago to not become an issue. Over the last 2 months i have been seeing a large shadow or m on the right side of my peripheral vision over 50x a day. As well when I sneeze I see sparkly white dots in my central vision. I called my Ophthalmologist about this to make an appt, the receptionist put me on hold for quite a while while talking to the doctor whom then told me this can be very serious. They were closing for the holiday so they were unable to make my appt until the opening of the office on tuesday. The doctor gave me an emergency number to reach him if my symptoms get worse. If I would have thought this was so serious, I would have called the doctor weeks ago. Is this a possibility that my symptoms can mean retinal detachment or is my ophthalmologist just taking precautions?