I have two apparently-contradictory pieces of general advice based on my own physio rehab from hospital bed to wheelchair to walking:

1. Don't overtrain.
2. If one movement is harder than the others, you've successfully identified the muscles that need the most work.

Consider lots of short sets on the front kegels, with long recovery breaks. Don't overtire them, but maybe do 5 extra stealthy front kegels + 10 sec holds once in a while when you're sitting at your desk, watching TV, etc., until the motion (including holding) becomes easy.

Best of luck!