Atypical secretion from right nipple.

It's been almost a year now since I've noticed secretion from my right breast nipple even though I've never been pregnant (20yrs old). The very first time it was a milky secretion half a pea size. I've not gone to a gynae till now, afraid of bad medicine side effects. I've noticed it secretes mostly when I'm aroused. It's a clear or cloudy white one when I'm slightly aroused n gets more milky when I'm intensely aroused. It doesn't secrete until I've pressed the nipple. I also have irregular periods, delayed by a week at least. I've recently told abt my condition to a general physician n he asked me to test my thyroid. I'm not getting time to go n show the reports (I've attached) on follow up. Can u please help me by giving an approx idea as a cause for my condition?