Watching my language

My language is a champon [mixture] of English and Japanese. When I’m speaking English, I throw in maybe 10% Japanese words or use Japanese constructions. If I speak Japanese, there are always English words in the mix.
It must be very confusing to anyone who doesn’t speak both languages. I’ll have to be careful when I leave Japan. Fortunately, everyone around me here does the same thing–mixes up languages at will.
Our vague utterances are always Japanese:
un – Yep
daijoubu? – OK? Are you OK? It that OK?
tadaima – Honey, I’m home.
iyada – No way, I won’t!
ie ie – No, no, no, no
hai – Yes
Sometimes what comes out of my mouth sounds like English, but it really isn’t. Most of the time, I’m not even aware that I’m not really speaking shizen na Eigo [natural English]. Here are some samples:
Must toilet! – I urgently need to use the restroom.
Let’s do sports – Let’s go to the gym.
She really levelled up – She improved dramatically.
I’m losing my English – I am losing my ability to speak and write fluently in English.
I would really like to keep my English, so I’d better level up on my use of shizen na Eigo.