Help: H1B-entering US without new I-94 card

Help!

I'm a Canadian citizen working in US on H1B, before exited US for a trip, I submitted my I-94 card together with the right side I-94 copy on I-797 (same numbers). When entering, I was told I don't need I-94, the flight attendant didn't give me one at all.

The Immigration officer looked at my I-797, asked two questions, stamped H1B on my Canadian passport without a date.

Will the old I-94 on the lower left side of I-797 with a valid date and number suffice or do I need to get a new I-94 at boarder ASAP.

Thanks, now l learned how important this small white card is.