Scared this could be serious.

I had a concussion a few months back but instead of my sypmtoms getting bettter theyve gotten worse. I get strange pains throughout my head at random times throughout the day, sometimes its almost like a shoooting pain while other times its more like pressure on my head. When this happens i get really dizzy and irritable. i am still having memory loss and sometimes i get really confused performing basic tasks. Ive also had trouble sleeping & my heart beats fast out of nowhere & i get occassional chest pain ? Do you think my concussion could have been a litte more serious then i & my doctor thought?