Baby refused BF all of a sudden

To give some background:

We have had an uphill battle when it comes to BFing. My son had a tongue and a lip tie, so has been getting a mixture of BF and bottle feeding (all breast milk). We had his tongue and lip tie revised, and weaned him off of nipple shields a few weeks ago. It was painful at first, but it seemed we finally got the hang of it without the nipple shields. He now is mainly BF.

The last few days he has been refusing to nap even though he is tired. He would fall asleep for 10-15 minutes after feedings and then wake up screaming. This would continue all day until 4pm, when he would fall asleep for hours. BF has also become painful again. Today he refused my breast and after several attempts I offered a bottle, which he took no problem and has been napping for half an hour so far.

Has anyone else had similar experience? What was the issue?

Note that LO is 11 weeks now. We did the stretches after revision for 4 weeks as instructed. Revision was at 4 weeks.