Well sms is the lousiest way, what if u sms her and she never
reply. You will be left wondering forever if she read the message,
or the message got lost.
Well whatever way, i think the most frustrating thing would be she
gave an uncertain answer. then it would be possible she not too
sure herself, or she is trying to reject but trying to do it in a
way so as not to hurt you. But if u can't get the correct message,
the woe to you.
Anyway good luck to you, if you muster enough courage to tell
her