Please help me out!! 😞

Jade • Jesus & Gypsy Soul 💕
So by the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> I was suppose to start my period on the 13th of March, Saturday the 17th I went to the bathroom, peed and wiped I noticed a light pink spotting on the toilet paper so I thought oh good my period is starting.. well nothing since then.. no other spotting, no nothing. I had sex on March 8th & 9th. I took a pregnancy test 2 days ago and It came back negative. 
My periods are very normal and if ever late only by a day or 2. 
I keep feeling like I’m going to start but then nothing, but ALSO I’ve been excercising I’ve dropped 20-30 lbs so far I’ve completely changed my diet and have been living a healthier lifestyle and going to the gym constantly and I know your diet can change your hormones as well. Soooo has anyone ever had this happen to them? I’m so confused if I took the test to early or if it’s just me and my diet changes, any feed back would help! Thank you!!!!Â