There's no silly question at a prenatal appointment. Writing down your questions as they come up during the week prevents the 'I forgot everything on the spot' moment — very common when the appointment is short and packed with tests to go over.
About your care
Which tests and ultrasounds are planned from now until birth, and in which weeks? Which vaccines are recommended at this stage (Tdap and flu are usually part of the pregnancy vaccination schedule)? What weight gain is expected in my case?
About daily life
What kinds of exercise are safe for me now? Are there any specific dietary restrictions in my case? Can I keep taking the medications I already use?
About warning signs
Which symptoms are reason to call before the next appointment, instead of waiting? Which number or service do I call outside business hours?