Glad you got that experience! It's certainly different than the full control-tower handling of an instrument approach at the final phases.
I had an unexpected variation of your event just a week ago, that's worth noting. Landed at KSDM/Brown Field, San Diego, at night, after 8pm, and the tower was closed.
I anticiapted that I'd need to land and call a tel#, or something, to cancel IFR once safe. Possibly, but probably not, SoCal might have a frequency that they could hear me on from the ground, but I put chances of that as SLIM. Instead, SoCal Approach said that they monitor and can respond on Brown Tower/CTAF after-hours!
Sure enough, I broke out, did a circle-to-land, while making standard radio calls. Once the wheels touched down, I announced on 128.25 that I was on-the-ground, safe, and would like to cancel IFR. The voice of the very same helpful SoCal controller came back, acknowledged my cancellation. I was really surprised and pleased.
Enjoy!!!