thank you Dr. Damien.
The hip problem seems to be significantly L>R wherein the R hip only occasionally acts up together with the L hip.
You mentioned that you would consider vascular issues... pardon my ignorance but what kinds of vascular issues would you be looking at in such a scenario? Necrosis? Just a simple case of vascular compression?
As for the back assessment, I avoided testing her back ROM too much because she was already presenting with high irritability and severity of the back pain at that moment. But yes, i will definitely come back with a thorough back assessment when i next assess her.
My pt's pains are not constant though its irritability levels are increasing as her condition seems to worsen. I think I might have phrased it wrongly - her 'aggravating factors' for her LBP:- lifting activities, stress, anger, fear/anxiety - are actually the provoking factors or mechanism of injury. Similarly, sitting in more than 80deg for more than half hour brings on the inguinal pain L>>R. After the onset of her pain(s), the same provocative factors for each pain respectively are her aggravating factors... am I confusing things? :S
After all has been said, your suggestion of a slowly progressing systemic problem does seem like a possibility. I have in mind SLE (lupus), early onset of arthritis.
I will also strongly recommend a lumbar/hip x-ray for starters (not as much a financial strain as an Wikipedia reference-linkMRI) and refer back to GP to rule out those systemic issues you mentioned.
I feel that priority should be given to the chronic LBP and this might provide some clues to the inguinal pain.

Once again, thank you for your suggestions. Will keep everyone posted on the progress.