@milkyman
He may have thought you were in your late 40's and so wondered if it was for contraception or HRT ... But why he needed to know just baffles me.
I don't mean to be rude about your age BTW, I am sure you don't look older than you are, but some people see and guess peoples ages differently IYSWIM. I am in my early 50's, and have been mistaken for 44-45 y.o, and have also been asked if I would like a senior citizen card by some bloody woman in a shop! 
So that obviously bloody short-sighted woman! thought I was over frikkin' 60!
In reality, I look 'roughly' my age. On a good day, with make up, a bit of a tan, and the grey roots covered at my temples, I could pass for 45, on a bad day (no make up, grey coming through etc,) I look 55-56.
Still struggling to fathom why he asked. Some of them are a tad nosey. My friend had very bad thrush in the summer, under her boobs, under her armpits, on her chest etc, and she was on very strong anti fungal tablets. The pharmacist was desperately fishing for where she has the severe fungal infection. 'We will have the other 7 tabs tomorrow' he said 'so here are 21 for now... So I guess your feet will be Ok with them for now. I guess it's your feet yeah?' 
My friend just smiled and said 'aawww thanks, I will be back tomorrow for the rest..'
Maybe they are just making conversation, but unless they are asked for advice, I don't understand why they need to fish. I know they have to ask certain things, like if you have taken them before, and if you are on other medication and so on. But the pharmacist did not need to know what your pill was for, OR what my friend's anti fungal cream was for.