Any disruption to a toddler's 'routine' will cause a change in how they sleep. For your little one is was a cold, and being allowed to sleep with Mom and Dad. My son and I are co-sleepers and whenever he got sick when he was younger, he'd get used to me cuddling him and holding him so he could breath and it was tough for him to break of that after he got better. Really it's not a tantrum, but confusion at this change to what she has gotten used to from being sick. But, it's okay at least you made sure your little one was comfortable and happy while she was sick...good work!
But, we got through it...with some conisistency, and patience so can you guys! For us, we slowly moved back into the regular schedule and did a lot of explaining. My son has his side of the bed, and it's designated with special blankets and his pillow. If I put him down on his side of the bed, he'd flip out and want to be held. So, for two weeks we moved from being cuddled and held to slowly placed on his blankets. If he 'freaked out', I would pick him up cuddle him and say 'Mommy is here and I love you, you're safe but now that you're feeling better you get to sleep on your blankets'. It was tough, but I repeated it over and over again. Eventually, he just stayed asleep. My friend recently had this issue, and she tried it with her little girl who crib sleeps and it worked in two weeks.
Really, it's tough because you do need your sleep, but your little one needs your help understanding and working through this change. Please try not to let her CIO, I'm not a fan of it and it really just sounds like she needs a little guidance from Mom and Dad.
Good luck!