I have a meeting soon.

　　I have an engagement soon.

　　I have an engagement very shortly.

　　I have a date very shortly.

　　I think I'd better go now.

　　I think I should go now.

　　I think I ought to go now.

　　I think I must go now.

　　It's getting dark.

　　It's getting dark outside.

　　I've to go quite soon.

　　I must go quite soon.

　　I must leave quite soon.

　　I've got to go/leave in a few minutes.

　　It was wonderful to get together again.

　　It was exciting to get together again.

　　It was exciting to talk to each other.