What happens when the Holy Spirit comes upon you? Well.... We don't know...
And God hath set some in the church, first apostles, secondarily prophets, thirdly teachers, after that miracles, then gifts of healings, helps, governments, diversities of tongues. Are all apostles? are all prophets? are all teachers? are all workers of miracles? - 1 Corinthians 12:28-29
You may be called to be an evangelist!
You may be called to be a teacher!
You may end up with the gift of miracles... Healings... Helps... Tongues
You may end up with the gift to play the piano!
But if the Holy Spirit come upon us and we all received the gift of playing the piano that would not be an exciting place at all. It is nice to allow the Holy Spirit to come upon us and see what unique gift he puts on us! It is exciting also to see what he does for others! But... We don't really know until we see the fruits of all of that!