TMI - Orange-ish Stain in Underwear

Apologies for the TMI early on a Monday morning.... I've just been to the bathroom and I've got a definite orange ish stain on my white underwear. It's not loads, perhaps a teaspoon amount? I don't remember this with my first but I have been feeling a little "off" having back pain/period like cramps over the weekend. I've dismissed these until now as they've not been in a pattern or worsening but now I'm questioning if this is something I should be flagging with the midwife as the colour has really thrown me.