I took birth control pills last year for 6 months for my PCOS and stopped then started taking them again a month ago but stopped again because of recently finding out about DVT. On my last pill, I started experiencing very mild aches in my left leg but it went away then 4 days ago I started having them again. Yesterday morning I noticed my left calf somewhat tightened. I would usually feel it after sitting down and then after walking for a couple of minutes, it would go away. But then last night as I was walking I felt a mild sharp pain on the back of my left knee that lasted for a second then went away. I suddenly felt light-headed and somewhat dizzy and my heart started beating faster and I couldn't breathe like usual. My left leg felt really tired as I was sitting down. But today I feel fine. I don't feel any pain on my leg. I have already gone to an internist and he didn't think there was anything wrong and said it was very unlikely to be DVT. What should I do? Should I be worried?