Early Pregnancy Symptoms at 31: What Could It Be?

Question
Hello, I am 31 and have had some strange things happen, which prompted
me to see my new ob/gyn.  Last Tuesday out of no where I would get very
nauseous very quickly and it happened again on Thursday.  My vision has
rapidly changes over the past few days, my lower back hurts, I'm having light
cramping and I don't get cramps when I get my periods and for the past few
days I have been exhausted and having bad headaches and just plain moody
lol.  Phew...having said that, I had sex with my boyfriend 2 times early
Monday morning about an hour apart.  The second time I noticed that I was
bleeding.  It lasted about 20 mins so I thought maybe I had gotten scratched
or something. Early Tues morning we had sex again, and again I had some
light pink/brown spotting for about an hour.  When I went to the doc today
they thought maybe I had polyups or a cyst so they did a transvaginal
ultrasound.  There were no polpus or cysts. The measurements are as
follows.  Uterus L-7.39cm W-4.47cm, H-3.93 Volume 67.92 Thickness 9.58.  
since Aug my cycles have been: AUG-SEPT- 28 days  SEPT/OCT - 26 days
OCT - 22 days NOV 13 days  My LMP started on 11/18.  I am not on birth
control and I have had an STD panel recently and I have HPV but nothing else.  
In July I was diagnosed w LGSIL/CIN1 and it has yet to be treated.  Since about
October 29th I have had sex almost every day with the exception of when I
had my period Oct 25-29 and Nov 18-22.  My doctor said that its possible I
could be pregnant since I had a lot of sex with my boyfriend during what he
believes was my ovulation time frame.  What are the chances that I am
pregnant, and when is the earilest I can find out?  Would the ultrasound today
have shown if I was?  Also, if its not polps, cysts, or anything else like an STD
or relating to the CIN1 do you have any ideas as to what may cause this new
post sex spotting?
TIA
Missy

Answer
Missy,
You really have a lot going on with you. I'm not sure all of it is related to each other. The change in vision and headaches concern me the worst. I think you should go to a regular doctor, like an Internist, not an OB for that.
Based on your LMP, I would think you can take a pregnancy test on the 16th. If that is negative, wait two or three more days and test again.
It might have been too early for them to view anything when they did your ultrasound.
Hope this helps a bit! Good luck!
Suzette