I realize I missed the diabetes in my summary (sorry!). I hope I'm not missing anything else. To answer your question, I have a hard time connecting the four issues you described (the diabetes, nose bleed, eye infection, and the mass) as one underlying disease. I am concerned, however, by the frequency of new illness/conditions popping up in what I assume to be a relatively healthy, although admittedly older, labrador.
My recommendation for you is to have a discussion with your family and your veterinarian about your goals for your dog, both short and long term. In the short term, you obviously want her to be comfortable and not be bleeding all over the house (reasonable goals for any pet owner). In the long term, if you want her to be as healthy as possible for as long as possible, you may want to consider working these issues up with additional diagnostics and treatment if indicated. By that I mean additional blood testing and imaging (possibly even a CT scan) to evaluate the cause of the nose bleed. Evaluation and sampling of the lump that recently appeared and is bothering her. Careful monitoring and continued treatment of her eye as indicated.
If, on the other hand, you and your family feel that your dog is getting older and is more frequently developing illnesses requiring treatment (frequent vet visits, medicine administration, etc), and you wish to discuss her overall quality of life and when to make the difficult decision to let her go, that may be valid too.
The path you choose will depend on where you and your family are at emotionally, physically, and financially with your dog. If you wish pursue testing, I think you should make an appointment for tomorrow morning with your vet as your dog sounds like she is bothered by the new lump, and rechecking the eye infection regularly is also advised.
I hope this answers your question. If you have any additional questions or would like clarification, please let me know!