Can you have a period after not having one for 18 months?

Yes, this is quite common we find. Officially you are 'through' the menopause after a year without periods, but we find that it's safer to wait 2 years without any before assuming you're through, as so many women tell us that they have another one or two after the initial year. Don't worry, you're unlikely to have more than one or maybe a couple.
 
Eileen Durward