Musculoskeletal issue or something else?

Ok, so I'll start from the beginning shall I? (warning, It's a bit long winded)

So, about 3ish years ago (when I was about 18ish) one day I remember I started to feel mild chest aching, Of course I feared the worst but I let it go, the next day I was feeling tingling down my arm and slight dizziness so I was like right, off to the hospital I go.

The pain is located in the middle of my chest around my sternum area by the way.

So I get to the hospital, they do an ECG/EKG, Blood Pressure, Blood Test, Chest X-Ray (to rule out infection) and general just feeling and listening around the chest etc. All of them came back negative, they said it was not anything to do with heart damage or anything like that(he said the tingling was probably my anxiety mimicking heart attack symptoms) and it was not a chest infection.

he said it could be some fluid around the heart, only a small enough amount that some Ibuprofen would get rid of it or it would have shown up in the X-Ray or it could be a musculoskeletal issue which the ibuprofen should also take care of, but he didn't seem too concerned really.

He prescribed me some Ibuprofen and sent me on my way, I took the Ibuprofen and for that week or so I was fine, but about 2 weeks or so after that it came back and it hasn't gone away since, now this isn't pain like ARGH!, it's a very stand-able and and mild pain (sort of like a dull headache, more annoying than anything), but it is constantly there and some days it's fine, some days it's noticeable and some days it's just down right annoying and when i push on my chest it makes it hurt a little bit more (in the way pushing on a sore muscle does).

Also sometimes it's not just a dull ache but feels like only a feeling I can describe as tension like, it feels really tight and I need to expand out my chest to almost relieve it or lean over the back of a chair or something.

I have always been overweight and have recently (4-5 months ago) started losing weight by exercising and eating right.

The pain doesn't really affect my exercising, I mainly do jogging, running, playing soccer and I also lift some weights too. My chest doesn't seem to affect me or hamper me while doing these. however sometimes (not always) when I am jogging if I go for a while after a while my chest starts to tense and tighten up a bit and I gotta rest for a bit, also the other day I lifted a carton of beer in such a way that it put most of the weight pressure of lifting it on my chest and I felt the dull ache a little more when I did that.

So basically It has been just like that since I have had it but recently (last 4ish weeks) I've noticed, sometimes the pain is a little bit different, still a dull ache but its slightly more sensitive and instead of needing to press on it to make it hurt more just turning and moving my chest around makes it hurt a little more and whenever this happens basically I lean over the back of my chair and move my arms out to the side of me and after a bit when i find the right position i will hear and feel a popping sound in my chest like cracking a knuckle or something (it doesn't hurt) and after that the pain dissipates and goes back to normal.

This extra sensitive and popping thing doesn't happen very often though maybe once or twice a week and it's generally in the morning after I've just woken up, but most of the time It's just generally the normal dull ache I've been talking about.

So yeah, that's my story, basically I am just over it now, anyone have the same or similar or know what it is and what I can do about it?

Sound like something someone knows about?

Any help would be appreciated,

Thanks, Daniel.