Psoriatic arthritis, like fibromyalgia, is hard to diagnose. But with a long history of psoriasis it's certainly a possibility you want to talk to your doctors about.
I had psoriasis for 20 years before I got arthritis. I think that's pretty common. I started with sore toes, and then moved on to the classic "sausage toe." I would eventually have four of those. Then my fingernails and toenails started lifting. This is a common sign that psoriasis is progressing to psA. After that it went to my knees, elbow, spine, heel, and a few fingers.
Before all this, my psoriasis was quite mild and easily treatable. Mine was on my legs and genitals, and usually cleared during the summer. I'd had the foot problems for over a year before anybody asked about psoriasis. It was actually a podiatrist that made the connection. My family doc was treating the foot problems with NSAIDs, and the psoriasis with steroids, but never put it together.
Since then I've been seen by two rheumatologists who both say I've got a classic case of PsA, but there is no specific test, just their judgement.
Finally, Enbrel and other drugs in its class are very expensive, but there are lots of other things they can try if you get a psA diagnosis. These biologic drugs are just one of many options.
Healing well with psoriasis, PsA, and hypogonadism, and happy to share my experiences.