This could be a vaginal infection or fungus. Yeast will react in this way, especially if you eat foods with sugar. I would check with my OB Gyn to make sure it is nothing critical. Your husband may be giving it to you also. Check in with your Dr.
I'm 52 and I have had exactly the same problem for seven months. I do not have a discharge and there is no unpleasant odour. It's extremely irritating, mostly at night. I use vagisil but it does little to help.
I'm 50 and have had irregular periods for two yrs. I have the exact problem. No other signs or symptoms. It does feel somewhat tender so I refrain from scrubbing when bathing. I pat myself dry when I tinkle cause I sure don't want to irritate the skin no matter how bad I want to scratch. I also wondered if I had pin worms cause of it being worse at night. So embarrassing and gross this is the only place I have mentioned this problem.
I have a similar problem. I have been peri-menopausal for a number of years. But now I am getting irregular periods and some "flash anger" and the last 4 months I get vaginal itch after sex. It goes away after a few days on its own. I don't have yeast and I actually do spot a little after sex just for that day and have a discharge that day only but no smell. I have normal PAP's and I'm going in for a pelvic in a couple of months for my annual physical so I'll tell the doctor. But a yeast infection wouldn't come on immediately. I don't have Bacterial vaginosis and I tried not washing with soap right on the vag area but it still does the same thing. So either it is vaginal dryness or maybe I'm allergic to the condom. We never wore condoms very much because I was on bc but I can't be on it now due to blood clots. I would say it may be vaginal dryness or lack of estrogen. But mine might be a allergy too. Hard to know.
FYI, yes pinworms are more common to itch badly at night or towards the morning but usually only in the anal area. They can do a "pinworm" paddle test. If you have more questions go to the Infectious disease site and I can explain more to you if you like.