What does implantation feel like???

Hello ladies. Im trying to concieve & it says that its best to BD a few days prior to ovulation. This app says i ovulated on the 9th of Oct & we BD on tues (cant BD everyday unfortunately but when i was ovulating we made sure we did at least 3x on that day) anywho.. Ive been feelin some menstrual pains the past week but i just recently had my period & then today i had like a really bad cramp on my left side. It was so unbrearable i couldnt stand up straight so i layed down until it went away. Idk how else to describe the pain but that it felt like air but more like a cramp from your period plus a cramp like from walking too long. I didnt walk today btw i was home all day. Can u share if youve experienced implantation pains?? Im not sure whats going on with my body right now😕 i am trying to concieve tho so any input would be greatly appreciated💜