As in what? What do your numbers look like?
What you might think is "fine" might be too low calorie wise for your energy demands. Honestly, your problem most likely stems from your nutritional habits. Try upping your calories by 500 kcals a day and see how you do the next time around.
I asked the first question because if all of your workouts resulted in you being weaker, it is almost definitely a result of either nutrition, stress, or lack of sleep (which I think you would be pretty easily aware of). So, how did your other days look in comparison to the first time through?
I asked for the rowing numbers because they might illustrate a muscle imbalance which could potentially be holding you back.