Side effects chemo

Hi I've been on treatment for a year now for stage 4 lung cancer with chemo pemetrexed & pembrolizumab. On my last 2 cycles which are 3 weekly I have had severe balance issues especially on my last round 3 weeks ago. 

I believe this is a side effect from chemo as have been to a & e this week & had head CT scan & was normal as we're my cognitive tests.This has really impacted on my quality of life as I feel like a drunk woman & I'm scared it will be permanent now. My treatment has been suspended until I see my oncologist asap.

Has anyone else had this & how have you coped & did it subside please? Thank you