"It seems to me" is most likely coming from the much less fancy sounding, and more casual "мне кажется" (mnye kazhetsya).
"Mnye" would be "to me", and "kazhetsya" could be represented as "it seems". I say "could be" because there is no direct translation for "kazhetsya" as far as I'm aware.
The closest (and most direct) translation of "kazhetsya" that I can think of, and retains the meaning would be "it seems likely that <...>".
What she was trying to communicate was "I think", I think. (pun intended)
First of all, I made a list of Russian я/мне lines with English translations next to them just to see if there is consistent presence of a hint in English lines that can point to the right Russian translation. There is none. So if you are trying to figure out the proper pronoun this way, you are doing it wrong.
To make an educated choice between я/мне you'll have to familiarise yourself with nominative and dative cases.
Here is some basic info on the cases in "question" and even more basic examples:
Nominative case of "I" is "я". Nominative case answers questions such as "who?" or "what?".
Кто пришёл? (Who came?) Я пришёл. (I came.)
Dative case of "I" is "мне". Dative case answers questions such as "to whom?" or "to what?".
Дать кому? (Give to whom?) Мне. (To me.)
As you might've noticed, native English speakers won't normally construct questions in a way they are constructed in most Russian cases, so I'd suggest to get familiar with cases and their respective questions first, and try to construct sentences later.
Or, depending on your goal, you can simply memorize common sentences/lines altogether and figure out why they work later.
Where I especially get mixed up with Russian is when dative and acusitive are in the same sentence. Next up for me is instrumental case - oh boy
He'd watched the series in German and then in English and knew it well enough to pick things up.
To my ear, his English was pretty good.
That said, the 2 groups of non-native speakers that have impressed me the most are people from Sweden and Norway. I've mistaken more than one of them for native speakers (to their delight) :D