Pre-labor shakes?

Are they a thing? I've heard of them but idk. I'm beginning to temor and shake like I'm cold uncontrollably. I haven't noticed any contractions  but all day I've been having TINY spots of blood in my underwear and I have upper back pain real bad. I'm concerned this is labor starting, my husband has people over drinking. Are pre labor shakes a real thing or has anyone had them??