You can tell the difference between GERD and anxiety by the symptoms. GERD symptoms are usually physically painful, like a pain in the chest, sore throat, burning or congestion in the sinuses, and the symptoms tend to occur over a long period of time. Anxiety can produce a lot of different symptoms with some of the most common being feeling worried and stressed, fast heart rate, strange feelings of pain that come and go. Sometimes the pain from GERD can cause anxiety, which is bad because anxiety usually makes the stomach produce more acid, which just makes the GERD more uncomfortable.
When trying to get your GERD under control, it's usually best to not be in a hurry to "fix it". It usually takes a long time to figure out the best way to treat it, so try to relax and take it one day at a time.
GERD doesn't usually go away on its own, so if you want to heal it you can first look at lifestyle changes. If you have obvious problems that make GERD worse, like an unhealthy diet, smoking, or being overweight, those would be things you can change. You should also make sure your PPI dosage is sufficient to allow any damage to heal. If the dose is too low, then more damage is being done everyday than your body can heal, and you will slowly get worse. Once you get the right dose, it can take many months before you really start to feel better since the damage takes a long time to heal.
If you exercise, you should be careful to only do it when your stomach is empty, otherwise it will force acid up out of your stomach. And don't do things like touching your toes since bending over can cause the acid to come out of the stomach.