The match against sheik, the chree guy mostly got some luckay kills. Sheik's up b is a kill move that counters our planking if we don't space it right and you weren't aware of it at the time so the moment he busted it out it worked. The second kill on you was a needle on your woi which almost never happens.
You seem to just not know the sheik matchup which is understandable as to why you lost. Sheik can be tough even when you do know how to play it. You just need to stop throwing out moves hoping they will hit and actually get punishes in. Really think about the situation before making your move. Sheik is a very fast character so any laggy moves (dsmash,fsmash, dask attack, glide attack) on her shield is asking to be punished. That thing you do where you smash, spot dodge, and then smash again while he just sits in his shield needs to stop too. Honestly don't use smash attacks at all in pressure situations like that. Best thing to do is gtfo by running or rolling away and shoot arrows to put the pressure all on her. The offstage pressure is going to be there because sheik can wall pretty good, just do the best you can to get back onstage. Careful with the uair planking though because that up b of hers can kill.
Summed up:
-Don't attack her shield so much
-Get more grabs in and pummel the appropriate amount of times as well
-Careful with your planking
-Spot dodge less in pressure situations
-Roll instead of spotdodge
-Be calm and wait for a spot dodge then time a good grab
-Get away as soon as you can when getting juggled
-Also don't throw out mirror shield or angel ring like that it doesn't really help you