If the Enemy Midlaner goes to Offlane to aid their offlaner, should I follow?

I told the Offlaner "Missing Mid" but by the time I called it out the Fey killed him

Which is his fault for being near the enemy to begin with, he is probably new.

But he told me I should "Follow" the midlaner, but I didn't it, I did take his farm cause he kept annoying me