Just diagnosed but unconvinced that I have this PsA thing...

I don't have psoriasis - but my brother does. My Dad had severe, widespread osteoarthritis and now I know more about PsA I would wonder whether he could have had it, but it was never diagnosed as such. I do have a lot of muscle/bone pain but I've had that for years - I'm 60. I do have X-ray evidence of osteoarthritis in the neck, back, hip and knee. I don't have nail problems other than my nails are weak and tear off easily. I have a painful but small lump on my second toe which a rheumatologist has said is dactylitis, and lumpy fingers. The rheumatologist said I have PsA after a 5 min history and 5 min examination. I've had negative blood tests for RA in the past. It depends where you're talking about regarding enthesitis. I don't have the classic Achilles heel/plantar stuff or the iliac crest but I have had all the others - patellar and quadriceps tendons, greater trochanter, lateral epicondyle, the small joints of the hands, and the supraspinatus tendon. So I meet the "Caspar" criteria but I just don't get how you can have this condition without psoriasis? I also don't get how seriously you need to take it, since it seems clear not much can be done for it, other than the usual "healthy living "advice, unless you want lots of side effects from painkillers. I probably will ask my GP to keep a sharper eye on my heart, and cholesterol levels. I wouldn't be allowed most of the DMARD treatments anyway, because I've had Guillain Barre syndrome in the past (yes that's an autoimmune thing). Mainly I feel this is being diagnosed because of one small toe lump which does not really even look like the dactylitis pictures on the Internet, although it has not responded to NSAIDs. I want to avoid "over-treatment". I tried to research prognosis, but because not many people have PsA without psoriasis it's hard to understand where this might go - again it just seems like don't eat, don't drink, exercise and hope for the best. So if you don't have psoriasis, are you reasonably likely to stay "mild", or no-one knows? Thanks for any advice. I do realise I'm lucky. I'm not saying I don't plough through a lot of pain and I'm starting to get life-limitations, but compared to people I see, I think I'm doing ok, so far. But the advice is all about "early diagnosis" and treatment to "slow progression" so maybe I'm heading in the wrong direction...?