Hi,
Do understand your fear. Based on the symptoms mentioned, looks like psychosomatic illness. Since you have written the brief outline of your issues, would be difficult to address it precisely. Panic attack can be due to life's incidents. You need to do self introspection and figure it out.
Next Steps
Would recommend to visit psychologist to help you address this problem.
Health Tips
(1) Understand your pattern of panic attack (2) Try to analyze when and where it all get started (3) Seek help from your loved ones