IVF and Pregnancy Reality

Anyone else ever go through the IVF process and not be able to get past that fear that at every visit your current reality is no longer going to be your reality.  I just did my first cycle of IVF in Feb/Mar of this year and got pregnant with twins after implanting two eggs.  When it takes so long and it's such a struggle to get to this point it seems almost unreal.  Not only that, but I'm into constantly convincing myself that it is not going to last because I'm so afraid of getting my heart broken again.  I had my first ultrasound appointment at 7 weeks at the end of May and it was the most amazing thing to hear those little heartbeats and see the two little fetuses.  While i waited for three weeks for my next appointment I literally had myself convinced it wasn't really going to happen.  Then my next appointment came, both still there, still with strong heart beats and normal growth patterns.  Now I'm in the waiting process for my next appointment, and despite my growing belly and all the symptoms I have I'm once again convinced it won't last.  I get so anxious going to these appointments.  I guess it's just hard to believe after so much time and effort that something so wonderful can actually be happening to me.