It really depends on how large the database is, but I dont think two days is nearly enough even with Access. You need to really plan it out well, because it's the type of thing where if you dont think ahead, you're going to have to redo quite a few things, which can be super time consuming. I should note that I'm not IT trained nor have I done IPT (I did do a unit in uni though), but I have built a HRIS (i.e. HR database) for a mid-size government department (800ish staff with around 70+ fields of data). To give you an idea, it's taken me about 40 man hours to build and I'm still modifying it at the moment.
The most difficult thing is probably importing all the data into the program, because you need to ensure data quality and consistency. Also, building forms is quite tedious, especially if you want to make changes afterwards. To be honest though, this is hard to avoid, because some things you just dont really realise until you are actually using the database.