I need some advice.

My six month old baby is suddenly waking up 2-3 times during the night, and I don't know why!

Some background: Last week she had a cold, and I assumed that she had trouble falling and staying asleep due to her congestion. I would suction her nose, and nurse her back to sleep. Now her cold is mostly gone, but we're still waking up 2-3 times per night. I try to comfort her without nursing, but it makes her mad.

She has been such a good sleeper up until this point. Usually 11 hours/night, and falling asleep on her own. She sleeps in a rock-n-play, which I know we need to get her out of (and will do this weekend since her sleep sucks anyway).

Any advice? Is this a prolonged six month growth spurt? Teething? Did I create an expectation for middle of the night nursing? Something else I can't see because I am so, so, so tired?

Please help Hellobee!