As a child, I was first taught Spanish. At school, it was difficult because I mostly knew Spanish and the basics of English. As the years went on, I began to forget some Spanish and relied on English. When my born-and-raised Colombian grandmother pointed that out, I practiced my Spanish to the point I forgot some English words. Now, I know English, Spanish, and American Sign Language. And I am currently teaching myself Japanese!
But being bilingual is wonderful because you are able to communicate with many new people, have a better chance of getting hired at new jobs, and so much more. Yet, there are benefits to growing up bilingual that people haven't told you about it, too.
Languages are intertwined with the culture of the language's origin. Knowing those two languages, you understand and might even practice both of those cultures. For me, I learned of Colombia's culture and language at the same time as being raised in the United States. Psychologists state that this opens an individual's brain to diversity and makes them have a better understanding of the world around them. This makes the person more sympathetic and empathetic towards others. Being a bilingual student is the best because bilinguals are above average when it comes to memorization and listening skills, like vocabulary and lecture lessons, as well. There are also medical advantages, like the fact it delays cognitive damage like Alzheimer's, dementia, and much more.
And the best part is, there are no disadvantages to learning new languages.
So, go open a book and learn a new language. Practicing could take around just ten minutes every day.