I want to breathe normally again. 3+ months ago I had pneumonia/bronchitis and now my asthma is getting worse. I'm on advair 100/50. I'm really scared?

Don't panic. First. See your pcp or a pulmonologist. Your advair diskis is at the lowest dose. It also comes 250/50 and 500/50. You may need to have it increased. A rescue inhaler will also be of use. Like albuterol or atrovent (ipratropium) or both (combivent). You should find out if your allergic to anything and then remove those triggers from your environment. Flu & pneumonia shots will help prevent catastrophe.
It is not uncommon. It is not uncommon for asthma to worsen after respiratory infections. Inhaled steroids can take several months to reduce airway inflammation. You should see your primary care physician and discuss your concerns.
See below. You may need to switch to advair via a metered dose inhaler also called a puffer (for example, advair 115). It is possible that the medicine in the disk advair is not getting down to the lower lung due to a problem with technique. A spacer or chamber will help deliver the inhaled medicine from a metered dose inhaler. You should also have a quick relief puffer like albuterol or proair.