sore nipple but no breast pain

i’m on depo and have been for about 8 months now. my next shot is due in 10 days. ive never had just sore or sensitive nipples some times my breasts will be sore for a week or so but not just my nipples. my boyfriend and i normally use condoms but if we don’t have them he’ll pull out. anyone have the same kind of symptoms or any advice? should i test? the last time we didn’t use a condom was about two weeks ago. could i possibly be pregnant?