Your measurments, are they in meters ?, if so then your looking at 26 sqm in total then, if that's how your working it out.
People often work out a price in different ways, and it's impossible to say exactly what we'd of charged for this job since we have not seen it, no idea if there are loads of tricky cuts that take time, or is it simple straight forward wall tiling with next to no cuts etc.
Now if it was 26 sqm plain simple level walls then I'd be looking at roughly 2 days tiling maximum then grouting the 3rd day, but your jobs over 3 different rooms, no idea of how many windows and placement and doors etc.
You mention floors too, is that included in your 4x4's etc ?
So without more information is isn't possible to tell really what the jobs really is.
Anyway, getting away from that, you are only just starting out doing jobs, and I guess this is possibly your first bigger job ?
Most people under estimate how long a job will take them early on, you think "oh yeah, I can knock this out in 4 days easy", then it takes 6 or 7

, don't worry about it, it happens, just another part of the learning curve.
Once you have finished the job, yeah you might walk away feeling peeved that you think you have worked for peanuts on it, but the experiance it has given you is priceless, because the next similar job you do an estimate on, you'll be able to compare it to this job you are doing now, and will have a better understanding on what was involved and will be able to work out your time frame better, and you'll end up earning a bit more too on the next job, plus you might be a little quicker.
All in all, I'd recommend mentally writing off your first 2 or 3 bigger jobs to experiance, and whatever you actually get paid in the end is just a bonus.
The annoyed feeling you get on your first couple of jobs that end up taking you a lot longer to complete that end up making you earn low rates per day goes after a week or so, you just write it off to experiance.
Anyway, tell us what sqm the walls and floor are and what's in the rooms, like how many windows, doors and what have you out of interest.