Palpitations. As if please suggest me!

Suffering with palipitations from 6 months contionusly. I am not getting any pain, no diziness, nothing. Done following tests 1. No of ECG's. All are normal except sinus tacycardia 2. Complete ECO is normal 3. Serum cartesol is normal 4. Thyroid is normal 5. Catecolomines is normal 6. 24 hr Holter Monitor normal 7. Thread mill test is normal 8. Mri Abdomen is normal. No adrenal gland issues All are normal, but palipitations not at all fetting controlled. Earlier used metxl. That didnt give any relief. Using prolomet 40 mg now. Giving relaxation. Met cardilogists and even Elecrophysilogy expert. All doctors are saying no need worry as it might be because of anxiety mostly as all the tests are normal. Do i need to really worry and consult any doctor or can i leave as if Please suggest me Thank you