The heater is really working now

I think my heating system is pushing dust around the house. I will admit it, I don’t get my heating equipment serviced. I just let the heater sit all year long stationary. It could have a ton of heater repairs and be filled with dust. I know that every year it turns on with no issue. I think I should have gotten a cleaning date though. My whole house is disgusting. I did a Fall cleaning right before I turned on my heating equipment. I washed all the rugs, sheets and dusted all my surfaces. I then turned on my heater and I noticed the house is gross again. The smell in the house is gross and stale. All of my furniture is coated in dust. The end tables are icky and my shelves have a layer of dusty film. I need to clean the whole house again. I am wondering if this is a one time dusting or if the heater will forever gross up my home. Will the dust just keep pumping out of the heater? Or has the heating equipment gotten rid of all the dust? I know that next year I will do a little more heater prep. I don’t know if I want to call an actual HVAC business to do a simple cleaning appointment. I think I could clean my heater on my own. How hard can it be? I just need to open it up, vacuum and dust the inside. It should not even take an hour. Even if it took five hours though, it would be worth not having a dusty home all year.