Tinted discharge

Has anyone had a tinted brown discharge really more like tan. Which would be old blood mixed with cervical mucus I think. My doctors told me I shouldn't worry because I don't have any cramping and that it could have been from sex. Well it went away for like two days and this morning it's back... We havnt had intercourse this time... So could it be from being constipated? Lol I guess with straining but the only time I did that was I think two days ago... Oh and I'm 7 weeks and 2 days