Nipple Discharge

I’m not pregnant, there’s no way that I can be, but I was squeezing my left breast and just fondling it a bit and some clear discharge came out of the nipple. I didn’t see it, I just felt it on my hand, so I squeezed it again and looked at it and saw a droplet coming out of it. It’s been about 5 months since I last had sex. Sex is always protected, & I’ve been having regular periods. I’m a little freaked out & I don’t know what this could be. Help!