I don’t know how you were able to load iOS 10.3.3 on an iPad 2 (2nd generation)?
An iPad 2 can only be upgraded to iOS 9.3.5 and no farther
Did you jailbreak this iPad?
Perhaps you own an iPad 4th gen, instead?
iOS 10.3.3 is no longer available for any downgrading hacks.
Apple stopped signing/supoorting iOS 10.3.3 7 months, ago.
At any rate,follow and combine my list of iPad performance tips here to help improve the performance of your iPad.
Tap on the link below to my iDevice/iOS performance/optimisation user tips link.
https://discussions.apple.com/docs/DOC-10344
Try all of these tips and leave each tip active together. Do not simply try every tip individually, expecting just one tip to be a performance “cure all”.
Many of these tips are designed to work together to improve overall iOS/iDevice performance.
Good Luck!