Hi Rin - I had this. I had spotting for 4 weeks, then had a big bright red gush (no cramping). Thankfully bubs was fine when I had an emergency ultrasound, and after the big bleed the spotting trailed off and finally stopped. As a precaution, I did go on basic bed rest for several weeks to give everything a chance to heal internally, and definitely no lifting! Also on my 5th pregnancy after having 3 consecutive miscarriages - so I know how it messes with your head! Really looking forward to my 20 week scan in a couple of weeks and hoping everything will look perfect and I can hopefully properly relax!
Hope this helps!