Don't confuse filing and service.  I am not a Florida attorney, but as I understand the rule there a party may serve interrogatories on the other party without filing them with the court, or without also filing proof of service at the same time. 

Proof of service only become an issue if someone doesn't respond to something they've been served, and it becomes necessary to default them or require them to take some step in response.  As indeed appears to have become the case here...  I imagine your attorney could now make a motion under Rule 1.380 as they have failed to answer the interrogatories in the required time.  At that point they'd probably need to file proof of service.

What you want to do is ask your attorney why the other party hasn't responded in the required time (counsel frequently agree not to strictly adhere to time limits for a variety of reasons), when you are going to get a response, and what the attorney will do now that the time has passed.