Why are my boobs always sore ?

Ok so I have been trying to conceive for 6 months now but have not got a bfp hope that's right I have been track as much as I can but not getting any where but it seems like my boobs are always sore and I have been lactating for almost two months now but it's not much but not understanding why do u think maybe I could be pregnant ? I had a period on time but only lasted about half the time as it usually is ? But really not getting why they are so sore ? Do u think maybe could be from ovulation ? Really been bothering me please help me maybe ideas why ???