I had the same surgery, tomorrow makes one month. There are still random pains, mystery phantom feelings, and my muscles and nerves have started to heal and have random impulses from time to time. Night time brings some of the interesting ones.
I found that eating the low residue diet recommended by my doctor to allow my gut to heal and taking a good health food probiotic helps keep the gas down. One of the things that can mess with your output is if you're taking meds, pain killers can alter your digestion and antibiotics can kill the good bacteria in your gut.
I had similar nights and found I ate something that was having an issue moving through and would cause pain and for some reason raised my output to be mostly liquid and gas, normally would pass with time.
Talking with my doctor and a family friend in the same situation, when you have your surgery, your stoma starts out bigger and over time will reduce in size. This is because your small intestines are swelling/inflamed from being operated on. This means the opening is smaller, not normal, but as it heals the stoma will reduce in size and your intestine will heal and go back to a normal size where food can pass through easier.
The phantom fart or pressure was explained to me that your gut is still wired to your muscles in your pelvis area, so even though there is no exit down there, the nerves still give a feeling when the gut is full. I understand that it gets less with time.
I wish you the best, fellow Texan, on your healing process.