What can cause persistent, slight pain on the lateral side of right breast with breast implants about 4 years after surgery?

I have had textured silicone breast implants for almost 4 years and within the last two weeks, I have had persistent, slight pain on the lateral side of my right breast and was wondering what this might be? My primary care physician examined my breast and said she found no lumps or swelling. Within the last month, I have also had neuropathy (tingling/numbness in right toes with some warm sensations in my right leg) and occasional lightheadedness.