Yes. People can develop allergies to anything at any age.
The way it was explained to me by an Allergist was that once the body reaches a certain “tipping point” from the cumulative effect, things which were not problematic in the past can suddenly become so.
This also explains the very rare cases of people who end up allergic to just about everything and have to live in specialized houses with elaborate filtration systems and other extraordinary measures.
This typically happens following exposure to a particularly noxious substance and their system becomes overloaded and just caves in. Then the simplest things which were not previously problematic provoke a major allergic response.
On a much smaller scale, that’s what happens to folks who develop allergies as adults.
If this problem persists past a week to 10 days, that’s most likely the reason.