Leaking Colostrum at week 18

Hi there!! I just wanted to ask if any other mummies here have harvested colostrum during their pregnancy before? I exclusively pumped for my daughter, then stopped pumping 3 months ago when I learned about my second pregnancy. My breasts "deflated" when I stopped pumping, but recently they have swollen again. The swelling reminds me of my previous experience with mastitis swelling, so I'm wondering if I can express some milk (colostrum) now to relieve the swollen feeling. In week 18 now - need some advice is have 🥲