The new battery you put in is fine and more than adequate compared to OEM. That is of course assuming battery itself is good as occasionally some are bad off the shelf.
The loss of power issue you are feeling is likely just the car re-learning air flow, mixtures and your driving style. Memory of this is lost when the power source is disconnected but it should revert back to what you're used to after 30-50 miles of driving.
That being said, you may want to check the battery and alternator using a DMM (digital multi meter). Place the probes across the battery terminals with the car not running and ignition off. Battery should read 12.6V. Repeat test w/ the car running at idle and the DMM should read 13.4-14.4V
Good luck and to help us trying to read your future posts, please use sentences and punctuation . . .
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