I Have Had 4 Visual Migraines In The Last 4

I have had 4 visual migraines in the last 4 weeks, and am 61 years of age. I previously had one episode about 10 years ago. I am very healthy, do not smoke, hardly ever drink and swim 2kM 3 times a week to keep fit. The symptoms are loss of sight and a feeling of mild confusion, aura that last about 10 to 15 minutes and then a mild headache. I last had an episode Monday last week but still have a mild headache. I visited my doctor who said it was just a migraine and not to worry unless I had more than one a week and prescribed a drug called rizatriptan. However, my daughter is also a daughter and is concerned that there could, given may age and the development at this time of life, should have had some more investigation to rule out other causes. My question is, do you agree, should I seek out a second opinion?