Palma plantar psoriasis & Nail loss

I’ve always suffered with a mild form of psoriasis, however 6 months after having my little boy and the stress of money etc I developed palma plantar psoriasis which is also affecting my nails. My toenails have tripled in thickness and misshaped and as of last night I lost my first finger nail which all appear to be becoming detached from my skin. I’m on methotrexate now and is start to improving my skin but my nails are just getting worse. Anyone had similar experiences and home remedies that could help. I would like another child so can’t stay on this medication long term as well so trying to change my ways of eating to see if it helps. Can you pay for allergen tests?