How to manage a project in oil and gas industry?

I am a new grad and i find myself unable to do anything technically in the project. I was hired as a project engineer and I am under a project manager. The project is small and cost approximately 400K pounds. The project manager is pretty busy with his other projects therefore I often try to work everything by myself. When i say that i mean, i try getting documents done and he’ll check it. I tried creating data sheets, request quotation, update the project schedule and budget, distribute tasks to discipline engineers, gather technical information to reply the customer’s enquiry. Those sort of thing. I don’t know how i fare as a young project engineer cause everyone is quite experience in projects. I am considering to change my job. Anyone out there having similar experience working in oil and gas projects? Some advise please?