sharp chest pain under left breast

I am a 21 year old female, with a BMI of 40.

5 months ago I visited the doctors with chest pain, which tended to be localized on both the right and left side of the sternum. The doctor took my blood pressure, which was normal and checked my heart rate, which was around 75 bpm. I was diagnosed with suspected Tietze's syndrome and sent home. However, I still have chest pain in the same area, and have also I began experiencing pain under my left breast and left armpit. The pain is dull and sharp and causes shooting pains in my chest when when you press on the sore areas, (I have pains under my right breats but not as bad). I was under the impression than Tietze's syndrome only lasts a matter of months and as I have these pains for months now I can't help but worry. Is it normal for the pain to stay this long? I have taken no meds for it, but can't help worrying this is more serious. If it was anything more sinister would my blood pressure have been too high/low?