Burst blood vessel in eye while lifting!!??

As above really. I wasn't lifting heavy but I do try to push myself. I walked 3 miles before the gym, cross trainer 30 mins quite hard then weights. I leg press 90kg, shoulder press 20 kg. Was leaving when caught sight of myself in the mirror. All is ok and eye has been checked out. I was told it is to do with raising blood pressure too high but I don't think I do that much???