I'm 4th months into my PhD and so far I havn't got any results and I'm not doing a lot lab work because I'm doing something quite new which is taking its time to get started. My supevisors havn't suggested anything else that I could do in conjunction. But now I'm starting to worry that I should be busier and find things to do in the meantime. Has anyone else had this problem?

Often, supervisor/s will give you a side project to work on at the same time. Sometimes, the side project works out better than the main one and can even become the main focus of your thesis! Discuss with your supervisors. Also, you can ideas for side projects by looking at papers related to your proposed project. Otherwise, getting started takes time. Important not to keep repeating the same thing. Think about what the basis for doing an experiment is and not just the result.

Hey Getting to grips with you phd subject matter can take quite a while, six months or so. Dont expect great results in the first while as it rarely happens and if it does your extremely lucky. Best of Luck