Could i be pregnant or what??????????

my last period was may 31st. my cycles are 28 days. so my next period was suppose to start june 27th but its now the 29th and i still havent started. so im only 3 days late. i took a pregnancy test yesterday and it was negative. i've also been feeling "wet" down there but no discharge. me and my boyfriend has been ttc for 3 months. could i be pregnant or is it my period coming? TIA