It's Mother's Day in UK!

Apparently, all these years I've been fundamentally mistaken. I assumed that Mother's Day is a universal celebration. I thought, globally, Mother's Day is celebrated in the second Sunday of May every year, that's how it's done in Malaysia. But this is not so in UK! Mother's Day here falls on 22nd of March each year. I am now stuck in this weird dilemma, do I wish my mom "Happy Mother's Day" on Sunday or should I do so in May? Maybe I should do it twice, hehe~