Week 16 with sore breast

Hi Fellow Mummies, Im currently in my 2nd pregnancy. During my first pregnancy i didn’t manage to latch my girl due to alot of contributing factor but i managed to express pump for her to be exclusively breastfeed. When i learn about my pregnancy 2 mths in, doc recommended me to stop pumping. Now that im in my wk16, i sense soreness in my breast again. Feels like the milk is starting to product again but one side of my boob is alot of “stuck”? I tried to squeeze abit and indeed one flows better and one is like perma stuck. Im afraid of mastitis again after birth. Not too sure if anyone experience anything similar and of you did, did you pump to release your breastmilk despite being just 16wks into pregnancy? I lve read online but they only advice to pump for colostrum in week 36. Helpps