"Now, Jesus did many other signs in the presence of the disciples, which are not written in this book; but these are written that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name." (John 20:30-31)
"…what signs I have done among them (the Egyptians), that you may know that I am the LORD." Exodus 10:2
God is sovereign over creation. He, therefore, can do things we cannot, such as heal the sick or fill the land with frogs. The Father and the Son both did these things to demonstrate their power and sovereignty so that men and women would believe in them. Pharaoh's heart was hardened by the display of God's power. The Jews also rejected Jesus despite the signs.
We did not get to see any of the signs. But God had them recorded for us by faithful men. Reading them we experience the same awe and believe in him. Those who believe receive the power to become children of God with eternal life. (John 1:12)
It may be a hard day. But eternity awaits.