Broken/Fractured first / second rib - UK Citizen but no insurance - Treatment cost?

Well, damn it.

Fell off my bike last friday (as in, a week ago today) and landed hard on my right side, which sadly is where I had my bike lock around my body. Long story short, I landed really hard, and I think I've fractured or broken a rib or two. The pain is getting worse and not better, and just because I'm an *extra* stupid idiot, I got back on my bike on that lovely sunny day we had at the start of the week and you guessed it, I crashed again. Equally hard. This time I ripped up my hand and elbow, and the impact of the crash made everything around my ribs/back feel much worse.

Now, I know that the treatment for cracked/broken ribs is basically painkillers unless you have a flail chest, which I don't think I do, but it hurts plenty, and its getting worse, not better. I'm worried that the break/fracture(s) are at the back, near the spine, not at the front or side, and there's a lot of nerves there, not to mention my spine! Which clever looking people have told me I'll need to keep in good working order as I age gracefully. (27 currently.)

If I go to hospital, say the mater hospital (nearest), how much will it cost me? I'm actually from the UK, born in London and grew up there, but have an Irish passport as my family is irish.

I havent lived in the UK for about 3 years, I remember getting some EHIC thing before I left, and I remember being told that now that I had it, all I'd have to give is my national insurance number if I ever wished to avail of its protection - and I know my national insurance number. The physical card, however, is long gone.

I doubt I'll need treatment. I'm pretty sure that they'll just say it either is, or is not broken/fractured, and tell me to take painkillers either way. But the fact that its getting worse, that I was in a second crash, and that its a first/second/third rib injury rather than a 'safer' middle rib, makes me think maybe I should go and get them to shine the radiation beam through me.

TLDR: How much for xrays and a radio' to look at the xrays if you're from the UK with an EHIC.