ill tortoise advice needed asap please

by paula walsh
(west yorkshire)

Ive bought a six year old male horsefield and hes in a bit of a state ive had to clip his beak hes underweight and has floppy legs hes really weak and not moving very much ive been putting food in his mouth been giving him water by seringe and have been giving him calcium he has picked up a little ive taken him to a pet shop who know a bit about him they say that im doing the right thing but can anyone advise me further i want to do my very best for him thanku paulax