Swollen and bruised hand

I have had mi series 3 watch for 3 months now, and the past few weeks my hand has started to swell plus a yellowish bruise is now appearing on the left side of my left hand, I do not wear the watch two fingers width from my wrist bone and definitely do not wear it to tight (the notch below makes the watch loose and wobble- notch up is way to tight) Iv had to take this off as my hand is quite painful to the touch... I’m disappointed as this was a treat to myself and I can’t be with my phone at work and having a father that is unwell the txt and phone call function was extremely useful for me... anyone else having the same issue.