Can I register my return to Thailand myself instead of my landlord, and is it legal for the officer to block my visa extension due to a late TM30 registration?

I have just had an interesting experience at Mae Sai Immigration Office.

I arrived at Chiang Rai Airport on Saturday. I immediately went to the Immigration Iffice nearby hoping to report my return. The Offices were closed. I presumed Mai Sai would also be closed as it was the weekend. (The Website actually states that both offices are closed on Saturday and Sunday) I went to the Mai Sai office first thing on Monday morning to register and to renew my Retirement Extension.

The Officer processing my application informed me that my Landlord should have contacted them within 24 hours and would now gave to pay an 800 baht fine. I explained that I had tried to Register at Chiang Rai but they were closed and presumed Mai Sai would also be closed. She insisted that they are open at weekends despite the times printed on the door ( Open Monday-Friday ) and the Website stating that they are closed Saturday and Sunday. She would not process my Extension Application until the fine was paid. I had to pay the 800 baht fine and my Visa/Extension was processed. I was not given a receipt for the fine. I didnt make a fuss or point out the anomalies in her actions, as I live here and didnt want to create future problems for myself as I always use this Office.

I have several questions. Am I able to register my return instead of my Landlord ( they are both quite old ) and was it in order for the Officer to block my Extension Application because of a spurious infringement.

Thanks.