Hi,
it should be "you were doing". At first I translated it as "you did", thinking the person meant it as the title of a film, but the word "veikei" (with a mistake in the given text) indicates that it was not an action which lasted merely a moment. if the word would be "darei" - then it would mean "you did".
Hello,
I agree with Dzuljeta. This form of Lithuanian verb implies some continuance (though it is not exactly the same tense as Past Continuous in English - we just don't have such a tense in Lithuanian). So it should be "you were doing". Though, in my opinion, in English "you did" somehow sounds better .
Valentina