I've Been Having Pain Behind My Left Knee, Plus A

I've been having pain behind my left knee, plus a tingley feelinf in my left hand ,just under my thumb, and the veins in my lett wrist are very much more pronounced than my right wrist. I have also had heart flutters. Should I be worried? My name is Heidi. I didn't realize this was a money sight. I was hoping for a quick answer. Sorry. Just wanted to know if I should see a doctor. I will keep searching online for answers. Thank you.