Neglecting to replace air conditioner filter leads to bad smell

I am not the best when it comes to keeping the house neat and tidy. I live alone, so it’s my own mess to deal with. I feel I can live anyway I want. That usually works out OK, but my laziness caught up with me when the house started to have an unpleasant odor. I went to visit my parents over a long weekend. When I returned home, there was a definitely stink in the air. I realized I needed to make some changes in my way of life. My mess was dangerously close to growing into squalor. The first thing I targeted was to get some natural ventilation. I opened up all the windows and started up all the fans. I figured that running the Air Conditioner at the same time would promote the airflow, but it only made the smell much worse. I realized that I had not changed the air filter for several months, maybe longer. I checked and found the filter totally clogged with dirt and grime. As I was changing the air filter, I noticed that there was a considerable accumulation of dust on the grates of the air vents. Every part of the air duct that I could see was filthy. This was partially because of my lack of household cleaning and partially due to my neglect of the air filter. Once I got everything properly cleaned, I turned the A/C up to the max capacity to get the air circulating. I then tackled the necessary cleaning. It took me several days to get everything clean and organized. Now, the house smells a lot better. It feels better too. I’m now a little concerned with the humidity levels. The A/C is struggling to handle the moisture. With everything so clean, I don’t want to deal with mold or mildew.
a/c serviceman