Phimosis or not? Or mild phimosis?

I have never retracted my foreskin as I didn't know about it till 30 years. My foreskin used to cover the head fully. But recently found out it can be  retracted over the head. So I started trying it. At first I was not able to but after few attempts, the foreskin did open to reveal the full head  but am afraid to fully open fearing it may get stuck behind the coronal ridge. Also I have some difficulty putting it back to original position it feels like skin is sucked in and fortunately it came back. During erect state my foreskin covers the glans fully so it does not retract automatically but I can slowly do manually  but am afraid to pull it back fully  during erect as it may get stuck. Is this a case of phimosis or mild phimosis? I don't have any pain while urinating or masturbating.