How old is he now?

Both my boys cluster fed int he afternoon/evening and it felt like they were contsantly feeding.
The best way to know he is getting enough is his nappies, not how oftne/long etc his feeds are. It could be that he is building up your supply for a gowth spurt, some of them may be comfort, or thirst, rather than hunger
I know this next part is easier said than done. I b/f both boys and had significantly different experiences.
The first was traumatic I was stressed all the time, beside myself when he awanted to feed all the time, worried I wouldnt have enough cos it was too close between feeds, he wasnt attaching properly etc.
The second time, I just fed him every time he wanted to. Somtimes that was hourly round the clock. Most days it as 8-10 times a day in the early days, but 5 of those might have been clustered together. Id did take a good few weeks for my nipples to stop being sore.
What are you using on them?