This is what i tell every 1 in this situation
1)stay down, check all the possibilities.
2)Check each vision, for any cameras, guards or other things.
3)Check out each guards routine walk.
4)if possible check out if hey go away and count down for how long.
5)go into stealth mode.
6)hide.
7)do not try and run forward just stab them if possible.
8)As soon as its possible hget out the crawl space and stab guards facing the other way.
9)try and try again.
10)dont give up.