So far, my pregnancy hasn't caused any ear imbalance. But I used to have this before I got married and even after. But my case was not as serious as yours.
What I had was feeling dizzy when I woke up in the morning, and all I could do was go back to sleep and wake up later again to see if the dizziness went away. I never had cold sweats though, unless I had my period and had menstrual cramps.
I believe you probably didn't "chor yuet" well after giving birth, or perhaps you were eating the wrong things for your body. If you have this ear imbalance problem and it is getting worse, you should pay attention to your eating habits and also your body condition. You may need more rest and sleep. Don't eat vegetables that are considered "cold" by Chinese medicine, like "bak choi"/tung kwa. Don't drink cold drinks with ice. Don't drink some vegetable soups that are considered "hon leung". Consult a Chinese medicine practitioner. Most of all, don't take too much western medicine, as they just stop the dizziness but don't solve the root problem. Hope this helps.