Is it anxiety?

For the past year and a half, I’ve been struggling with something but still don’t have a diagnosis.

Increased heart rate while walking (100–160 bpm), and even at rest (80–90 bpm).

Pain or stabbing sensations in the chest area, especially on the left side near the armpit and toward the shoulder — particularly after meals. The upper part of my chest muscle sometimes “twitches,” which feels very uncomfortable and always makes me think it’s a heart problem.

Pressure in the sinuses (upper part of the nose) and a feeling as if I can’t breathe properly through my nose.