Diet and/or hormone changes or vaginal infections could all affect vaginal scent. It's good that it's not a foul odor and that you have no discharge or discomfort, which could indicate infection. If it's due to the drinking or perhaps going into pre-menopause, is hard to say without an exam and/or blood work up.
So best case is it may be natural for your body if there are changes going on.
Worst case, possible infection, pH balance may be off as well. I don't know if you douche on a regular basis etc. Try eating some yogurt, as this helps to bring pH balance back to normal. If there is a change with your urine or a sweet smell in the urine as well, this can indicate sugar. I know you said your work hours vary. Perhaps you can even get checked at an after hours clinic which is generally open till around 8p or later. So that is an option as well.
Other wise, hope this helps and gives you some ideas as well. If you need anything else please feel free to ask. If you found this helpful don’t forget to click the *Accept* button.
Without any tests there is no way to pin point the exact case of what may or may not be going on. You asked for best/worst case scenario, which you were given.
Things we eat can cause a change in the pH balance. Citrus, fruits, juice, can cause a sweeter smell. While things such as. Things such as coffee, beer, dairy can give an odd scent. Everyone is different, so what may be for one, won't be for the other etc. If a persons body is dehydrated vs hydrated this can effect the smell. Hormones imbalance can effect smell as well.
Diabetes or uncontrolled sugars can effect this as well.
But if you knew these, then you know you need to find away to be seen. Unless things have changed recently in your diet etc. especially if this is something new for you. Do keep in mind, some woman have a natural sweet smell, while others may have a musky smell. It's just how the pH balance is set up.
Hope this helps. If you need anything else please ask, as I will help all I can.