the brown watery discharge sounds like your period is ending or beginning to start. All women's discharge are very different. I've experienced a huge amount of discharge everyday and I was scared so I went to get a STD test. All my symptoms came back negative and said that is just my normal everyday discharge. Now if you are not using a condom it is likely to catch a STD. I suggest you go get tested if you are not sure about your partner
I used to have yeast infection and i know how it feels but this time it's not itchy or hurting so...don't think it's that
This might be signs of a yeast infection. If you've never had one you should probably see a GP or OB/GYN before buying anything over the counter.