negative urine and blood test but havent gotten my pd yet

hi, im ttc and i thought that this month was the month. i have just started tracking my ovulation and periods. my husband and i had sex during ovulation. about 2 weeks later i had light pinkish brown spotting for about 3 days, something that ive never had before but sounded a lot like implantation bleeding to me. i waited about a week to two weeks to take a hpt, theyve all come out negative. my husband said that my chest looked much bigger (first thing he noticed when he walked in the door) ive been so exhausted, wanting to sleep in every day possible and taking naps which i only ever do if i am sick. there have been a fews days at work where my stomach felt upset but i dont know if im just imagining it because i want to be pregnant. also been very thirsty. but as i said all the tests have come back negative. and i also had a blood test done that was negatove. it has been 35 days since the start of my last pd. which was the end of march. my periods are pretty regular (dont know exactly how long my cycle is though) but i know i always get one each month and theres only 1 more day in the month. do you think its possible that i am pregnant and testing too soon, or that the blood test could be wrong? i had the blood test done 5 days ago. ive never had anything like the IB so that is why i am confused! thanks!