Behaviour Change At 11 Years Old Siamese Cat, Please Help

Hello all. After exploiting all the Vets I wanted to ask here.
I have a 11 year old Siamese. She was normal (as much as they can be ) until 6 months ago. Then something changed. She started flicking her tail up every time, jogging all of a sudden, grooming her fur non stop and also scratching herself until she opens wounds... Licking concrete is also something she started doing... Also, she stop caring will she hurt anyone. Before she would jump on your naked back and you would not be injured. Now, she dose not care and just jumps on people and scratching them really badly. I tried Vets, bus as I live in one smaller town is Serbia, they were not able to help. I am wondering should I cut her claws to see will this help for a first thing to stop injuring herself and other. Please if you have some experience, share or some suggestion.

Thanks

Is she kept indoors? I have always trimmed the claws on mine, even though they have scratching posts. Have you recently changed her food? Has something changed in her environment?

can your vet test her for hyperthyroid? are there any antianxiety meds they can prescribe? trimming her claws can't hurt. I think those can also be signs of food allergy. is thereh any vet you can drive her too that may be better but a further drive? it really sounds like it might be worth it. does she have fleas? it could be a flea allergy too.

is she eating normally? drinking normally? Urinating and poohing normally? has she lost or gained weight?

the licking concrete is called pica

Unusual Cat Cravings: Why Is My Cat Eating That?

you should get her tested for felv and fiv if she's an outdoor/indoor cat.

As a further thought ive had a few cats that use pica as a way of communicating that they require food or water