Is this my milk already?

Lily • My gorgeous little boy due 8th of March 2018💙

Ok so when I was 17+6 I had a yellowish stain in my bra where my nipple was and I rang my mum straight away panicking, she said her milk came in early and to press my boob to see if anything came out, and a clear liquid did, and ever since I did that my right boob is absolutely killing me!! It’s my first baby, can anyone relate?? I’m 18+4 now😊is