When implantation occurs do you always have to bleed?

ive read everyone saying that when implantation occurs you have tiny bit of blood when you wipe or you have a little bit of brown color when you wipe my question is could you still be pregnant if you didnt get blood or color brown when wiping cause me and my hubby BD on my around ovulation time or on the day of im not sure but is there still a possibility i might be pregnant because right now i believe i am either 7 or 8 days DPO and im going to wait till the 22nd to test so im hoping to get a BFP..but i did not get any blood or any brown when i wiped since we BD but i have had slight cramping and i have never got that before I have my period but im do to start my period on the 22nd and i know i cant have signs this early even if i turn out prego but i have been getting really nauseous too only when riding in the car but that could just be motion sickness which i dont get unless riding rollercoasters so i thought it was wierd but beside being nauseous and slight cramps i just have super tender but that usually happens when i get close to PMS time =) im not stressing like normal im actually really calm especially when im this close to testing but any advise on the implantation stuff would be very much appreciated thankyou so much in advance have an awesome day/night! =)