A few weeks ago I had a short spasm in the middle of my chest, it lasted just a fee seconds but I am left with a dull ache in my chest.

Exam. It's worth looking into. We had a motto at our emergency room that pain, or even just strange sensations, above the waist were cardiac until proven otherwise. Get an exam and a discussion with a health care professional. Better safe than sorry. Unlike the old days, there are now so many things you can do to prevent or stop heart problems.