Another Migraine, First One In Four Weeks

The other morning (July 30th) I had my first migraine in four weeks. When I went to bed I had a terrible neck ache, so I took vicodin and slept most of the night. I woke up around 6 a.m. with a migraine. Of course my migraine was accompanied by nausea and vomiting. I stayed in bed for most of the day, getting up occassionally to eat and throw up.
In the evening I stilll didn't feel well, I felt warm, so I just went to bed early. The next morning I felt better, but I didn't really get up until mid-morning.
Tomorrow I will be 12 weeks pregnant and on thursday (August 6th) I will go for my 2nd ultrasound. This one will be a fetal anotomy exam. I am excited about being able to see the babies again. I keep looking online for websites with gestational fetal growth charts. I want to see how my babies are changing from week to week. I've found a few sites where I can see what I'm looking for, but most of them focus on singleton births. I want to find websites that only focus on twins and mulitiple births.
I wonder if anyone pregnant with twins had an ultrasound at 12 weeks (and 3 days) and was able to see the gender of their babies. Also, if they could see the gender, and if the sonographer was correct about what they saw. If my upcoming sonogram is an anatomy exam, will they be looking for gender? This is all new to me, so I don't really know what to expect. I am excited and can't wait to see what I'm having. I want to go shopping so badly, but I want to wait until we know what we are having. We kept looking at the chinese gender calendars, but they were all so conflicting. Some calendars said, boy and some said girl, this made us laugh and say, they must be twins, a boy and a girl. I think it will be a boy and a girl, that's what I really want, but their daddy wants them to be boys, our son wants boys and our daughter wants girls...go figure. Of course we want two healthy babies no matter what they are.