I think you should go for it. But I also think you should do some planning though so you get the most out of your adventure. I spent a summer in Spain - 3 months several years ago; was on Tenerife working at the University for 4 months this year and vacation there quite frequently.
1. Consider a formal study of Spanish. If you are from outside the EU you can get a visa to be in Spain for an extended period of time if you go to study the language in a qualified program, EU people can just go there with no visa. I would go to a nearby University where you live and find out if the Spanish Department can recommend a good language school in Spain. I would go for a full-time course, meaning at least 4-6 hours a day - 5 days a week, of Spanish classes. That way you will learn Spanish in a more systematic and quicker way. Also you will meet friends. (Non-EU folk only can be there on 3-month tourist visas unless they apply for a longer visa. Most need PROOF of acceptance into a language program before the visa is granted from your home country. There are short term classes too, like Berlitz, that offer courses on a monthly basis.)
2. You could go to Spain on a 1-2 year AU PAIR contract! Yes, guys can do that too! I live in Scandinavia now, and one of the ladies in my circle of friends had a male au pair! Au pairs usually take care of children and/or do light house work. There are also au pairs that take care of elderly people while their adult children are at work.
3. You could just travel and stay in youth hostels. And/or you could take the 6 week El Camino - St James Walk in Northern Spain (starts in France and ends in Santiago de la Compostela). You stay at Pilgrim Hostels along the way. Earn a lot of money BEFORE you go to Spain so you have something to live on. You could work Monday to Friday at one job and then Saturday and Sunday at another job. Get a book like: Lets Go Spain. There you will learn about cheaper hotles and other bargins.
I recommend you need at least 2 weeks in Barcelona; 1 week in Madrid, a couple of days in: Toledo; Segovia, Salamaca; Granada, Cordoba; Valencia, Santiago de la Compostela. And there is the Beach!
4. Jobs are hard to get in Spain these days. The unemployment rate is over 20%. There are lots of young people unable to get jobs, even with a University education. The only thing I can think of is that you look into companies where you live now who are in the tourist industry serving people from your country that go to Spain. Like here we have Star Tour, Apollo, Thomas Cook and Ving that are Charter companies offering charter flights and hotels in Spain (Alicante, Mallorca and the Canary Islands). They need people to get the tourists on the buses and to their hotels, etc. Perhaps your country has Charter Companies. You get hired, take their short course, and then start working!
5. Housing: Youth hostels, a language school might be able to help you, the Guide books have cheaper hotels, go to your local charter company and see if they have LONG-TERM rates! I know I can stay on Cypress for 3-4 months only a few thousand dollars in the winter off-season months, including airfare!
6. Are you a bar-tender? There still seemed to be bar-tending jobs the last time I was in Tenerife last winter- spring for 4 months on business. I've also heard that Alicante and Mallorca in the summer hire bar-tenders and waitors from EU countries.
Have a great adventure!
Me. My life.