Depending upon the severity of ur symptoms, Behaviour Therapy called as ERP can be started. Thought stopping, aversive techniques can be adopted.
If none of those helps, u might have to be started on medicines.
Next Steps
Firstly u need confirmation of ur diagnosis, by an expert. Symptoms occurring suddenly after a long gap of 15yrs is unlikely. Perhaps u have had persistent mild symptoms.
If the symptoms are tolerable, u must try relaxation techniques with ERP.
Health Tips
Stress often increases symptoms, so u need to adopt stress-buster habits like Meditation, Pranayama, Yoga, Singing, dancing, sports activities anything that suits ur likes.