Girly, please talk to mom and this is why;
if u r 13; r u going to ask 10 yr olds to help u
mom has 1000 times your experience
I will give u this, your vagina is SELF CLEANING and every month your uterus has to build a NEST or home for the possibility that u get impregnated and when u don't it has to LIQUIFY that home and discharge it from your body. now thru out the month your cervix produces fluids that r appropriate for the particular time and they change from clear to yellow to next-to-nothing to thick-n-slick etc
NOW AS TO A YEAST INFECTION; it will itch terribly and be somewhat like cottage cheese and have an odor
as to other problems such as vaginosis which is completely different from yeast because yeast is fungal and requires ANTI-FUNGALS and the other is BACTERIAL and requires antibiotics
and then u could go on to many other possibles
SO IF IN THE FUTURE u have a question then u need only be specific and ask and there r lots of really smart people willing to help BUT DON'T FORGET mom is already there and has already been where u r at long time ago as has your aunts, grandmas etc.
best wishes to u