I'm doing some translations and I was wondering, what is the verb "приехать" related to? Is it just like English, where it means "coming, getting to someplace"? or, like English, can also have other meanings? Is it with a mean of transport ?
This is the article about another meaning of verb "приехали" ("Приехали!", "Здрасьте, приехали!").
But this meaning is not applied in your sentence "я думала еще приехать".
In your case the sentence may has three meanings:
"Я думала еще приехать" = "Я думала приехать еще раз", she decided to come once again.
or "Я думала еще приехать" = "Я даже хотела приехать, но не смогла". She even wanted to come, but she couldn't.
or "Я думала еще приехать" = "Я думала об этом (приехать еще раз), но пока не решила". She thought about it (to come once again), but she hasn't decided yet.
All three meanings here just "coming, getting to someplace".