5 hrs (not yrs!) should not be considered as a cause for concern. Address
this site to watch live where your transaction is in the queue of the memory pool.
Just a small correction, there is no such thing as "the memory pool" since this can and will differ between full nodes. So the sight you are referring to is the mempool from blockchair's point of view.
Sure, that is the common knowledge and me was expected everyone should be acquainted with that. BTW, I guess you wouldn't be surprise to learn that nodes exchange info relevant to their "mempools". I am not aware of algo which blockchair uses to watch for "mempool" but my own transactions have been found there in all cases when they waited for the "proper block".