Implantation bleeding advice

Hi everyone, so my partner and I have been together almost a year, we’re ttc and at the end of the month (October) during my fertile time we had sex a couple times. So in the following weeks I started getting nauseated very easily especially around certain smells. I was due for my period but was late and this past Sunday I started to spot. It was a pinkish brown color and I had very mild cramping then late Sunday night there was some bright red blood. Into Monday there was only a little bit of blood and it tapered off into the light pink/brown again. Typically I’m not late and my period starts as spotting but then with a few hours becomes a heavy flow with crippling cramping and stays consistently heavy for about 3 days and ends with 5/6 days. Can any share their experiences? I just want some advice before I get a test or go to my dr. TIA.