The first foreign language may be a hard nut to crack, but when you've already got the tools, the new languages get absorbed much more easily. I speak 4 other languages besides my native Russian and Ukrainian.
I had that experience too. I began studying Spanish when I was eleven. Then when I went on to study German, Russian, Yiddish and Chinese formally, and several other languages informally, it was much easier.
BTW, got a question to you all. I observed an interesting phenomenon while learning Hebrew. During the process of learning, I felt I was losing grip of my French and German. Someone said it happened because Hebrew was a language belonging to a different family (Semitic, unlike all other languages I know, which are Indo-European). It was claimed to be the reason for its "aggressive" behavior - I mean squeezing other languages out. Have you ever heard of any such theory?
I have not heard of that and I certainly did not have that experience myself. Chinese is in the Sino-Tibetan family, whose differences from Indo-European, IMO, are much greater than the Semitic family: no adjectives, adverbs or prepositions; no gender, number or tense; in fact no inflections at all: even pronouns are gender-neutral.
I found, on the contrary, that having my world view expanded by exposure to the Chinese way of analyzing things, people, events and concepts improved the clarity of my thinking in all of my other languages. For example, I no longer thoughtlessly use the pronoun "she" to refer to a teacher or a nurse and "he" for a corporate president, and I miss the different words for "older brother" and "younger brother" or "maternal grandmother" and "paternal grandmother" when describing family relationships.
One of the things I certainly got from Chinese was an improvement in my conscious understanding and unconscious use of phonetics. Everyone knows about tone being phonemic in Chinese, but it has other phonetic paradigms that are quite foreign to Indo-European speakers; for example there are no voiced stops, but aspiration is phonemic; and stretched-out Z and ZH are both vowels.
This is something you surely experienced when learning English, because our language has more phonemes than most, even Russian with its palatalized consonants. Our two kinds of TH are tongue-twisters for most people, and it's quite a challenge to hear the differences between our huge array of vowels. One of my Russian friends still pronounces the name of the state Ohio as uh-KHAY-uh, and no one has any idea what he's talking about.
But you surely did not have this experience with Hebrew. Modern Israeli Hebrew is basically liturgical Hebrew, a language that was dead for more than 2,000 years and used only in religious ceremonies. As such, the pronunciation of the words was adjusted to the phonetics of the languages spoken by the Jews in the Diaspora, originally Aramaic but more recently German and Russian. The phonemes represented by the letters Aleph and Ghayin (now spelled Ayin)--a glottal stop and an uvular fricative--are now silent. Daleth and Tau, dental consonants as in Russian, have become alveolar as in German and English. Ghimel (with no dot), a voiced velar fricative, has become a G, and Qoph, a voiceless uvular stop, has become a K. Waw, a semivowel, has become V and is now spelled Vav. Vowels have been elided, especially the Schwa, so four-syllable words become two or three syllables. The stress, which used to fall more often on the last syllable, has shifted to the first or second.
Modern Israeli Hebrew sounds more like an Indo-European language because it was crafted by people who spoke Indo-European languages in an era when there was no voice recording technology. Ancient Hebrew sounded much more like its close relative, Arabic.