@tinka21 did you check your BG with a finger prick before treating the hypo and to check your recovery?
LIbre are brilliant but, like all CGMs, they have limitations.
For example, they may report low when you apply pressure such as lying on them when you are asleep and taking longer to report a hypo recovery.
Your levels may have gone hight because you treated a false hypo or because you over treated as you were waiting for the Libre to tell you that your levels were over 4.
Due to CGM limitations, it is recommended to always check highs and lows before treating unless you are feeling very low.