Aww mama, yun ang colostrum na (the yellowish fluid bago ang actual milk), normal lang yan at sign na ang body mo ay nag-prepare na for breastfeeding! Just keep it clean and dry, and the tenderness on the left side is also pretty normal kasi different ang development ng bawat breast, but honestly because you're experiencing discharge at pain na, better check with your OB or midwife lang to make sure everything is progressing okay, a few of us first-time moms had similar concerns at mas na-ease kami after getting cleared by the doctor, plus they can give you tips on proper care bago pa mag-latch ang baby. You're doing great na nag-ask, at excited na akong para sa inyo!