(I apologize in advance if this is in the wrong forum.)

I booked a round trip flight from NYC to Grenada, and there are layovers in both directions of about 55 minutes. On the way to Grenada, the layover is in Miami, so while 55 minutes may be tight, I feel pretty good about making it. On the way back, we'll have a 50-minute layover in San Juan, Puerto Rico. I don't know why it didn't occur to me beforehand, but will I have to go through customs in San Juan? If so, I can't imagine how we will possibly make it through in time.