I think it's pretty normal. This is my second and I am way more anxious this time, maybe because we know what to expect and are more knowledgable?! I'm much more aware of what can go wrong this time, just by reading articles posted on social media and through friends experiences.
It's awful but try to stay positive. I use milestones (we've just hit 24 weeks) and I have a 4D scan booked in a few weeks time. It breaks up the waiting game and makes me feel like I'm getting reassurance regularly.
I agree with keeping busy!