where do i turn to next?hat is your advice?

Diagnosed last Dec(13) with psa, been on methotrexate tablets, made me feel sick so been changed to injections, however feeling sick again so think my consultant will change meds again and I also take sulphasalazine. Waiting to physio therapy and seen occupational therapist. I am continually drained, not sleeping at night, and although not in much bad pain and I constantly stiff. I try to carry on as normal, but now I am even struggling to work, I deliver skips.my wife says I am becoming dangerous when driving, hands slip of driving wheel, wrists locking during hard turn, and knee locking whilst pressing clutch so stalled vehicle. Ot were great but due to nature of job not much adaptations to job available. I have recently put in a claim for PIP, but unsure if I will qualify, but not sure for how much longer I will be able to work winter around the corner and my work days are spent in the wet and cold but I am unable to do office work..... help!!!! any advise greatly appreciated, don't know where to turn next