Talk to Gynecologist on GP/ Gynecologist

I have a severe abdominal pain during periods and I get fainted, with dizziness and low BP and even low sugar level. I loss my concience and feel the noises in the ear. I always get out of it after 5-10 minutes by taking anything sweet , milk, dates and egg. But the pain in the abdominal area stays for about half an hour and it is very severe. I always have this problem once in a year, and everytime I notice whenever I have weakness, fatigue, stress, tension, deprived sleep and periods, I face this problem. But this time I had all this but after one week of periods and I felt too much pain in lower abdomen but it just went away in 30 minutes like it nerve happened ever. My bp was 90/56 but couldn't check sugar at that moment. After that I feel myself all fine with no symptoms at all. When I visited Dr two years back , she diagnosed low iron level and prescribed me iron supplements. This time I didn't visit any doctor , just asking should I consult General Practitioner or gynecologist