Where to go if a Spanish landlord won't do the repairs

I am having trouble with my Spanish landlady. When I took possession of the flat, there were a number of essentials I had to buy and there was no inventory provided at the time of signing the contract. The woman sacked the agent immediatly I arrived to take occupancy 6 weeks later, with whom I got on well and trusted. Since my arrival the shower has worked properly for only about 2 weeks, the toilet cistern is faulty and I have had to disconnect the float. to avoid water costs.

The TV is old and I cannot adjust the volume. I need a decent TV to try and learn the Spanis language.

On Sunday the mirror in the bathroom fell off the wall whilst I was out. I found it smashed and lying in the bath. I took it to a glazier as it is the only mirror in the very badly equipped apartment. He said it should never have been fixed as it was with hooks so I got them to put a note as to how it should be so that she wouldn't say it was my fault and therefore my responsibility to repair.

She had a couple of cheap cowboys who temporarily fixed things which now need re-doing but hasn't come to inspect the problems and is now ignoring my messages voicing my complaints. I told her to get things fixed as I am paying too much for so many inconveniences. I haven't yet paid this month's rent as I am hoping to put pressure on her to do the repairs and to pay for the mirror which I am obliged to do.

I was told I would get an inventory when I arrived and paid the first month's rent in May but there wasn't one. The previous tenants had apparently done a lot of damage e.g to the furniture and the floor tiles. This woman just doesn't care about anyone but herself and the agent more or less said that that was the reason for their dispute and she wouldn't want to work for her again.

What can I do to force her to do something to make it a comfortable place to live?

I am due to return to England in November until next year but am fearful she won't relinquish the deposit?