That was the first time an American complimented me on my English. I was quite happy.
That was the very first time an American person told me my English was good, it made me so happy.
この場合、次のような言い方ができますよ。
ーThat was the first time an American complimented me on my English. I was quite happy.
「アメリカ人に英語を褒められたのは初めてで、すごい嬉しかった」
an American complimented me on my English. 「アメリカ人が私の英語を褒めた」
ーThat was the very first time an American person told me my English was good, it made me so happy.
「アメリカ人に英語が上手だと言われたのは
初めてで、すごく嬉しかった」
an American person told me my English was good「アメリカ人は私の英語が上手だと言った」
ご参考まで！
I was so happy the first time an American complimented me on my English.
I was so happy the first time an American said my English was good.
「初めてアメリカ人に英語を褒められてうれしかった」は英語で「I was so happy the first time an American complimented me on my English.」と言います。「complimented」のほかに「praised」や「said ~ was good」でも使えます。「said my English was good」は、大体同じ意味ですが、相手に「good」や「well」などと言われなかったらあまり使えません。
初めてアメリカ人に英語を褒められてうれしかった。
I was so happy the first time an American said my English was good.
カナダ 
