Strange spotting ttc

I am due to start my period today. My predicted ovulation date was May 12th and last Sunday I had very light cramping. My period is always extremely regular occasionally starting a day or two early but RARELY later than predicted. I had a D&C due to a miscarriage in October and only had one late period since then. Today I had some cream colored yellowish stringy and slimey discharge (very minimal amount) with one small strip of blood in it. When I start my period I always get either pink/brown discharge or a small amount of just blood and severe cramping. This has been it today and I’ve never had that happen. I took a test and it was negative. My first pregnancy (successful) I tested positive two days late and my last pregnancy (unsuccessful) I tested negative three days before expected period and got a positive two days after I missed it. The discharge with the streak of blood in it has me thrown. Has anybody else had this before a period or before a positive test?? It’s never happened to me and I’ve always had a regular period. Been TTC for 6 months with no luck and we’re both healthy.