Musical instruments!?

i played the recorder and the flute for 3 years now and by morning i decided to buy a ukulele...because on you tube the instrument sounds good.! but when i bought mine it sounds different? is that normal ,i cant feel my fingers... and it sounds really different... is this correct"low,lower,lowest,highest" from the strings from the ukulele?or the ukulele i bought aint good? (cost 20bucks)???