I have all of a sudden had a feeling where it feels like a thump in my upper chest/throat area & when i have felt my pulse when this happens, it skips a beat & i feel like i dont take a breath for a second. i have been under stress, is it that?

Possibly: These symptoms are characteristic of premature beats or extrasystoles that cause a pause and then a stronger normal beat follows the pause which gives you the thumping sensation. Anxiety or stress may cause them, but if you experience these frequently, I recommend consulting a cardiologist to determine the type and frequency premature beats even though most are benign. Minimize alcohol,caffeine,