in need of a little advice :)

So heres my situation my fiance and I aren't avidly TTC were trying the lazy way of if it happen it happens so we don't stress out I do want another baby how ever I'm a little worried at the moment my last period started January 23rd and it was about 9 days long started kind of light then got very heavy this is normal for me I'm am currently three days late not unusual but for about the past eight days I've had some very weird spotting it started very faint pink then turned light brown which usually happens the day before my period but it never got any heavier it has gone from light pink to brown to a very bright red but not ever enough for a pad or tampon it only shows when I wipe (sorry bout tmi) and tonight my fiance and had sex and it got heavier for less then 20 min and has just about gone completely I've had very mild cramping and a pinching feeling that comes and goes since and feel a little nauseaand for that past eight days I just don't feel right and I'm not sure what think I have a doc app in a week or so but was wondering if anyone has had anything similar or could shed some light on what's going on ty