my son has character, much personality

hi, my son is 17 months, nearly 18, but since early he was showed like very self-sufficient. He wants to do everything by himself, sometimes it get me proud, but others, when he goes through a tamtrum for wanting something, oh... it takes me out.
Now a days, when he doesn´t want to do something, he throws himself onto the floor. I hardly take him from the floor and I put him on his feet.
other times only telling him: get to your feet, pull up, pull up!!! it works... each time it is more frecuent see him on the floor, either crying or shouting.
when I watch him in that sort of manner, I think fussy of him.