I had to self cath after my sling surgery too. It started at 4 times a day for a couple of weeks then the number of self-cath per day went down. For the last 4 weeks (of 8 weeks total self cathing), I self cath at bedtime only.
The medical supply company did not contact me before sending the second 90 day supply and I had to send them back because I did not need them.