Breast pains??

Soo. I bought a hippie hoodie about 2 weeks ago. So i just started wearing it without a bra everyday. Today i didnt wear it but wore a bra. Now ive had sharp sharp pains in my left breast. its happened occasionally throughout the day and when it does happen it happens on and off for like 5 mins. Is this because of the bra(nothing wrong w fitting) or??