Got a car or gotten a car

That's not what we'd say in England. You can repeat it as many times as you want, but that won't change things. In both of your examples we would say got. Although your second example is a bit clumsy, and I'd say, 'I've been getting up before seven all week,'

In American and Canadian English, the past participle of the verb get is usually gotten. For example, we might say, “I have gotten behind on my work,” or, “The book was not gotten easily.” Got is the participle in some uses, though, such as where has got to or have got to means must (e.g., “We have got to go to the store.”) and where has got or have got means has or have (e.g., “I have got five sisters.”)

In the main varieties of English from outside North America, the past participle of get in all its senses is usually got. Gotten appears occasionally, and it is standard in a few set phrases such as ill-gotten gains, but the shorter form prevails by a large margin.

That gotten is primarily used in North America has given rise to the mistaken belief that it is American in origin and hence new and inferior. But gotten is in fact an old form, predating the United States and Canada by several centuries. It fell out of favor in British English by the 18th century, but it was eventually picked up again on the other side of the Atlantic, perhaps by analogy with forgotten.

The vehemence of some Britons’ scorn for gotten likely has to do with the fact that it has gained ground in British English over the last couple of decades. Many English speakers from outside North America resist the encroachment of so-called Americanisms (many of which, like gotten, are not actually American in origin) on their versions of English, and, for mysterious reasons, some feel especially strongly about gotten.

( o' clock is redundant, very rarely used in spoken English.)

I had a mate who used to say things like "I'll meet you at the watering station at nine of the clock to consume libations of the brewed variety". A twat, in other words. The sun was either over, or not yet, over the yard-arm, the morning was 'the forenoon', etc etc.

I am writing back because I am having problems understanding the kind of English you speak. Are you from England?

Also, in the sentence "I've got up at seven all week", is "got" the past participle of "get"?

the Beatles

As said previously, in conversation, in the UK today, the use of 'o clock is redundant.