The human brain can handle up to 7 things at the same time. Anything more than that and you start to forget what the others were, or to do something specific (unless reminded of it) etc
You said that it appears that others seem to remember things automatically while it's a conscious process for you. I feel this is because you never developed (or tried to develop) your long term memory or skill at remembering things. This is usually a lack of enthusiasm at life that causes this IMO. And you're clearly not a fan of music (neither am I btw, takes me YEARS to learn a song by just listening to it) so don't worry about remembering that. You must have some kind of hobby that requires memory? And do you often forget things with your hobby as well? (I'm willing to bet "no"). That is why I said "enthusiasm". Something you enjoy will lead to better memory AT that simply because you like it and want to
The rest you have to practice!
Timelines, especially when you're getting older, do get blurry. In fact if you had to wake me up right now and ask me what year this is I'd most probably think "2009". It gets even worse when you don't "stop and smell the roses" so to speak.
Your ability to recall things, especially in the workplace, should be your primary focus for now. I'm not sure if you remember this, but in English/Afrikaans (or whatever languages you had in school) they had a test where you read through a story (once or multiple times) and asked you questions on it. That was an exercise in memory. If your job is so mundane and boring to you I can fully understand why you don't remember certain things, but in the long term and in your career path as you get older this can have quite a significant impact on your performance grades at work (I use the term "grade", loosely). So unless you're the bosses son and guaranteed a pay-rise every year for the next 20 years & the business after the old man kicks it, I'd start with basic exercises:
1) Look at a photo/picture for 10 seconds. Then close your eyes and try to keep the image in your head as it looked like when you just looked at it. Try to time yourself. As soon as it starts to fade try a new picture and try to keep it in your minds-eye for as long as possible. Try to increase that over time.
2) Puzzles. You might have seen a puzzle of blocks that they give you a couple of seconds to look at and then they flip on their backs and you have to find each of their twins? Play that game! The better you get the less time you need to look at it in the beginning the less "flips" you'll have as well. You're probably on facebook, so I'm sure there's a game like that somewhere.
3) Try to make conscious decisions to remember specific things *daily*. Don't try and do a marathon-length rememba-thon. For example, appointments. Try to remember at least ONE appointment for the next day. Then the next morning, without looking at your calendars, try to remember the appointment. What time, with who, about what. Increase that as you get more comfortable at remembering things (practice practice practice... that is ALL memory is)
4) Take it a step further. Come tomorrow, try to remember what you did the previous day. Start with something simple like WHAT YOU HAD FOR SUPPER!!! Once you start to recall that with ease, start going through your day starting with what you did when you got up, how the meeting went with XYZ and about what and what tasks you performed during the day etc
5) Increase the time span. Instead of recalling appointments for the day in the morning or remembering events (try to do that chronologically btw) that happened the day before, try to ADD and subtract a day. So if you're on Wednesday, try to remember all the appointments you have for Thursday AND Friday. Come Thursday, try to recall the same appointments for the day and Friday etc. Same with previous days. If you're on Wednesday, try to run through in your mind (writing things down as you try to remember it helps some people) what happened Tuesday AND Monday.
6) Try to understand what you're doing. If you don't understand and you don't make an effort TO understand something specific then you're more likely not to be able to recall it.
7) And for **** sakes just LOOK at the TV monitor at karaoke nights! THE LYRICS ARE ON THERE!!
I'm not that bad. At least I remember to breathe now and then 
Felt bad because the dude was probably waiting for me and I even had it set on my calendar. I was actually working late that evening anyway.
