Implantation bleeding or early period?

[Dokazz]

My ovulation was 13 days ago and I was feeling pregnant with all symptoms, cramps , lower back pain , nausea, headache, tired, smell sensitive , but last night, i had painful cramps with bleeding like a light period but the color is brown and light red or pinky and its not heavy , it doesn’t fill my pad i just wipe with paper and find the light red blood . I’m afraid I’m not pregnant. .

Is it possible it’s an implantation bleeding ?