Arniece, it has been my experience in the many years of traveling to Spain that medical insurance really is not as important as it is here in the U.S. - where if you don't have it you might not get the medical attention you need. Spain like Canada too, has public free healthcare.
As a former Spanish professor with many student trips to Spain and multiple medical issues - from a broken ankle, a hairline shin fracture, and many sunburn kids who wanted to get a tan disregarding the sunscreen advice, I can tell you that we were never charged a penny for the clinic/hospital visits we made.
And, personally, on the Camino Portugués I had to see a doctor in Padrón because of knee pain and get an injection. Total cost for the doctor's visit, and the steroid injection was 34€ and the prescription for pain medicine plus Omeprazole for 10 days was 4€.
On the Camino del Norte as I left Irún I met, and occasionally walked with an American young lady who after the first 10 days was in such pain she could barely walk, so we stopped in Laredo - where we stayed at the convent and immediately went to the hospital (I was her interpreter) They took x-rays, and told her she had shin splints, gave her crutches, pain medicine and told her to stop walking and rest. The charge? Nothing! The wonderful nuns allowed her to stay at the convent for 2 more days, She was not able to finish the camino, but she took the bus and we met again in Santillana del Mar for a day. She made the best of it, and actually signed up for a Spanish program in Alicante for the rest of her stay before flying back home to Texas.
Sorry I made this so long, but I want to reassure you that you really don't have to be overly concerned about medical insurance. Spain has amazing health care and they will take care of you at a minimal cost, if any.