A sharp pain for 30 secs or so, like muscle spasm, extending from left chest to left shoulder and neck. Same muscle tightness taking deep breaths 30 mins after the initial pain, should I worry?

You are young. Of course, people tend to worry about left chest pain being cardiac in origin. This would not be common at your age (but not impossible). In broad overview, sharp, short pains are less often of serious cause unless pain is quite severe and/or associated with other abnormalities. Ultimately, cannot diagnose this way; so, if concerned then have it evaluated.