The Barcelona team is becoming a mess gradually. The bad results is getting too much. They have allowed the praises and accolades they were getting at the beginning of the season get into their head. They became too comfortable and were not working hard to improve further. Now they have found themselves in a difficult situation.
Of course, Flick's strategy did not work well. I feel happy to see the loss. This is because Real Madrid has a chance to return to take over the top. Real Madrid still have 2 fewer matches. So the opportunity to seize the top is very open. I didn't see it directly, but I read these statistics and it looks very ineffective. Barcelona had 27 attempts on kicks and 5 for La Palmas. Barcelona's weaknesses are really taken advantage of by making a quick counterattack strategy. 
I was sure Barcelona could miss three points after i saw their line up before the game started. They played without their good defenders(Araujo, Christensen) and goalie (Ter Stegen). If they keep repeat the same mistake, all of madrid fans are feeling so happy with this.
The defeat at home against Palmas was certainly a big surprise and this further indicates that Barcelona is not as strong as they were praised at the beginning of the season, and what they are experiencing now is not surprising to me and it is even possible that this situation will continue because it is not easy for a team to rise from its slump.
And on the other hand, I see Barcelona's defeat opening up the opportunity for fierce competition with Real Madrid, now the two points are 4 points apart and Real Madrid still has 2 matches left which allows Real Madrid to displace Barcelona at the top of the standings.