iPhone lagging after update?

Hi everyone.

Recently I updated my iPhone 12 Pro Max to iOS 17.5 and just before that I had bought myself 2 TB of iCloud. Ever since i've done these two things my phone has been overheating (not to the point of locking but to the point of becoming slow and lagging, its fine once It cools down) and has been losing battery very rapidly! Im genuinely worried, because I like my phone and therefore don't necessarily feel like buying a new one. Has anybody else experienced such problems with their not-the-newest iPhones? If not, what do you think I should do?