If you only arrived on 17th October (the same day as me, coincidentally) surely it took a few days to open your bank account and deposit the required 800,000 Baht? As this has to be in your account for 2 full months, the earliest you can apply for the 1 year extension would be around 24th December. I say this because I am in exactly the same position - unless of course you already had a Thai Bank account with the necessary funds in place? This is not clear from your original post.

Blúport Hua Hin

Visa, passport, residence certificate from immigration. Kasikorn bank were very helpful.