HI , thanks for using healthcare magic
It is understandable to be concerned.
Some medications can cause weight gain, it can occur in different ways : (1) increase in appetite (2)decrease energy and activity levels (3) change in metabolism
Though it may seem so to you at the moment, it is unlikely that there has been permanent damage, it is just sometimes very difficult to lose weight especially on your own.
You can try on your own again or get assistance either by joining a group, seeing a nutritionist or bariatrician (
weight loss doctor), online weight loss program.
On your own , you can try using a low carb or low calorie/low fat diet whichever best suits you.
You would need to be able to stick to which ever option for at least 6 mts- 1 yr. Meal options are for either of these are available online.
A food diary noting everything that you eat or drink would be helpful.
Exercise for at least 150 mins a week would also be helpful
I hope this helps