After 4 month of getting 4 upper front veneers I’m still in pain and discomfort. What do I need to do next?

The pain you described, it is abnormal to last this long. Sometimes people can have a sensitivity which can last up to 6 months. There is a variety of possible problems;  you may need root canals, could be excess cement causing gum infection or irritation, occlusion problem, and possible clenching or grinding problem. Lastly, you may consider getting a 2nd opinion.

Photographs offer a great deal of help in everything that we do.  I would hope that your dentist took photos of your teeth before, during the procedure, with your temporaries in place, and after with new veneers. Also keeping the study models of what your teeth looked like before and comparing them to a study model of your teeth with the veneers in place.
When dentists who are very well trained in cosmetics do veneers we always know where we start, how you speak, the length of your front teeth before, and compare them to the length we prescribed to the lab for the veneers.  It is critical that we measure the length in your temporaries. It is very simple to analyze this way, along with your symptoms, and figure out what went wrong. Were your veneers done to lengthen short teeth? How is your speech? Also, how was your bite prior to veneers, and is it the same now, or does it feel awkward?
My very last question is important. How did your temporaries feel and look? Were you in pain immediately after the preparation, while in temps? Then there may have been over-preparation, meaning too much tooth was taken away, getting close to the nerve. That would not show up on an x-ray yet.
I am truly sorry that you had to go through this, all to seek a better smile