Hand express while pregnant

I'm 31 weeks and Ive been leaking a bit of colostrum for a few weeks already. Tonight I decided to use a new sterile syringe to suck it up while I squeeze my nipples. I was almost able to get 1ML of colostrum. I know what some may say.... Nipple stimulation can cause contractions and preterm labor.... But I just wanted to collect what i can because I had a very very hard time trying to BF my 17 month old when she was born. I had no clue on how to express colostrum or latch her properly. So this time i want to be somewhat prepared? I put it in a baggy and put it in the freezer. I actually wish I had that 1ML of colostrum when my baby got pink eye 3 months ago. I don't plan to pump it out, only hand express. And i won't dont it often at all. Anyone save colostrum while pregnant?