I didn't have symptoms and I'm 18 weeks and everything is fine. So don't worry too much.
all preagnancy are different with my 1st pregnancy i got the symptoms when i was 8 weeks with my twin girls i got the symptoms the last two months this is my third pregnancy currently 19 weeks and havent had any symptoms at all
Not having symptoms isnt rare or something to worry about, I didnt with my first 3 babies, consider yourself lucky =), congratulations!