Relapse?

I am a 37 year old who had my first episode 4 years ago of right sided pins and needles and altered sensation in my arm and then foot. Then followed up by L'Hermittes sign which joined in soon after. I wasn't able to be diagnosed officially as i didn't meet the criteria in Australia for a diagnosis despite having active lesions (both brain and cervical spine) on MRI. I was officially diagnosed 1 year ago after having more activity (new lesion) on MRI but no new clinical symptoms. I have been going along for 4 years without more symptoms (just the same ones which is generally sensory and heat related, some fatigue). Last week i developed left sided numbness in my hand and foot and some weakness in my hand. My walking has been affected as i am very cautious with the bottom of my foot being numb. Also unable to function properly due to terrible fatigue, which is a lot more than normal for me. My question is this: my MRI i had a few days ago hasn't shown any new lesions. The neurologist doesn't seem to want to treat me with steroids as the is nothing on the MRI. Is it possible to have a relapse or episode without new lesions? And in your experience do they benefit from treatment or do you just wait and see? I was really surprised i didn't have any new lesions as my symptoms are so obvious i thought there must be something happening. Is this a pseudo-exacerbation? I've not experienced this before so any input would be greatly appreciated. I would like to do whatever i can to get back to normal and working again.

Thank you for your time