my dog is ill...

[sheila2155]

my 14 yr old collie cross is straining to pee, peeing very little and doing it every few minutes. has had xray bladder which was nad. she also looks like she's in pain in one back leg. her tail has been between her legs for months now - she's very unhappy. had antibiotics but made no difference. any body help? already cost �400 and i'm no nearer to finding out what's wrong.

[petexpert]

put her down maybe its sighns of death or surgery for her bladder.