I'm a med/surg nurse educator and believe me when I say you know more than you think you do. We don't float our new grads for 6 months so maybe your manager can consider something like that? If not, trust that your assessment skills will develop over time and you will worry a little less over your patients as that happens. Confidence comes with time and experience.
Prioritize and delegate!! Not everthing is number one priority, you will drive yourself mad trying to be everything to everyone at the same time. Treating pain comes first for example, watering and repositioning patients can be delegated to a CNA when you are busy.
Pin a timer to your uniform--when you tell a patient you will be back in 15 minutes to address their request or answer questions, let them see you set your timer and return when it goes off. When patients know you are true to your word, they will sit on that call light less often. Patients who are anxious and doubt their nurses are often needy patients. You can buy yourself some time to do more critical things in that 15 minutes with another patient.
Until you get faster at charting, chart the important things first..assessments. Care plan updates can wait. Though they are important in charting, assessment documentation comes first.
Organize your area, stuff your pockets with flushes and alcohol pads if you don't already. Little things but it's one less trip out of the room.
As a new grad, I did up a template on WORD with a time frame and an acronym for charting things (P for PIE, O for orders, A for assessment and R for report). I jotted down what I had to do at each time from meds to things I wanted to assess specifically and it has been a life saver. No double checking and triple checking to see if I did this or that; it's been checked off my list. A lot of other nurses have adopted it too so if you want, I can send it to you as an attachment and you can adopt or discard if you already have something similiar.
Hope this helps!! Remember, you are going through what we all have gone through!! This too shall pass!