The risks of twin pregnancies are very real and sometimes scary but it's good to be aware of them now in order to be as prepared as possible, with the help of your OBGYN, your perinotologist and a local hospital that can handle high-risk cases.
We are very lucky that we have all this modern technology, ultrasounds and testing to assist doctors - forty years ago when I was born (I'm an identical twin) the only resource doctors had were X rays right before the birth to find out the position of the babies. There was no way to analyze other risks. Even with this lack of information, my mom carried us successfully to term.
I'm carrying twins too (fraternal). As my doctor sid, "make no mistake about it, twin pregnancies are not a walk in the park, they are high risk". Although my case is less risky than yours I have other pre-existing conditions that require constant monitoring. I was basically told to be ready starting at 24 weeks in case I went into preterm labor or I had to have strict bedrest. Going to the hospital, talking with the nurses and with other moms who've had preemies has helped. So has making a to-do list of what to have ready by then has also helped, a lot of the stress comes from what happens if there's an emergency and you are unprepared.
See if there's a local multiples club that you can join. I've found the moms to be incredibly supportive and helpful. No other mom except a mom of multiples can really understand what your're going through, especially in this day and age of celebrities with twins such as Angelina Jolie and J. Lo who seemed to breeze through their pregnancies effortlessly in long gowns and high heels.
In the meantime, you might want to read "Your High-Risk Pregnancy" - I found it helpful in learning about different risk factors, recommendations, bedrest, etc. and helped put my mind at ease a bit, as well as make a list of questions for my doctors.
An excellent doctor and hospital in your area is Dr Joanne Stone of Mt Sinai, one of the most highly regarded OBGYNs for high risk cases including multiples.