Spotting with cramps

I will be 13 weeks on Thursday and I’ve been spotting very light brown for the past week on and off! As of last night I started experiencing very mild cramping but enough to notice that I am cramping. This morning my light brown spotting turned into dark brown… I will be calling my ob as soon as the office opens, but I’m wondering if anyone can give me any insight or experience with this that continued to have a healthy pregnancy.

Side note I had my first bleed at 10 weeks with dark red brown and went to the ER. Everything looked perfect. I saw the baby and heartbeat nobody could give me answers as to why I was bleeding…. I had a follow up with my doctor a couple days later, and he did another ultrasound and everything checked out perfect again… the bleeding stopped then a couple days later came back! I’ve been on pelvic rest since the first bleed.