Which One Shall I Call My First Language?

I am an Indian (citizen of India). I have learned both English and Hindi since birth. Actually, my mom usually spoke with me in Hindi and my dad usually spoke with me in English so that I could learn English well. Currently, I have native like fluency in both the languages. I use only English at work and both English and Hindi at home almost equally. So should I consider myself bilingual or have a clear cut distinction between first and second languages.