Some verbs are less likely to be used in the past progressive, for instance "want"; though they do occur, e.g.
1. I was wanting to speak to Mr Q.
where the past progressive indicates a more "deferential" utterance than the more direct simple past ("I wanted to speak to Mr Q).
"I was being" is relatively common, to express "a past state in progress", e.g.
2. "Do you really think I look beautiful tonight?" "Actually, no; I was being sarcastic."
It can also form part of the past progressive passive:
3. I dreamt I was being chased by an enormous Adverb with a ferocious suffix.
All the best,
- For Teachers