Hi. Welcome to English Forums. I'm not a guru, just make a try.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
Cool BreezeMy apologies for the i
1. To express regret about a present situation, the past tense is used, as you say. However, for this situation you need the continuous past tense in your sentence:
I wish / If only I were going to America! (I'm going somewhere else at the moment.)