Is that a good decision?
There's no one who can really answer the question of whether or not you did the right thing except you. But without a time machine to reverse your decision, why agonize about it? You'll find out soon enough. Gear can be sold/returned as well as purchased. It doesn't sound like you made a grievous error and if you did, it's easily rectified as used 18-55s are easily found cheap.
Every newcomer to interchangeable lens system cameras has a "chicken and the egg" dilemma going on. To know what lenses you need, you need experience with lenses. But everyone is different. Everyone has a different budget, a different set of subjects they're interested in, and their own individual ways of shooting. So, whatever you need is individual, and you need to tailor your choices for your own needs.
Folks online can freely spend your money when they recommend lenses. They're also more liable to recommend what worked for them. You are not them. Keep that in mind. For example, the first lens I had to buy out of the gate was an 8mm circular fisheye. I'm very eccentric and I bought a dSLR to learn to shoot 360x180 panoramas. For 99.9% of shooters, my choice was dead wrong. But it was dead right for me.
Will I need the 18-55 lens?
The 18-55 is more of a vacation I-was-there snapshot lens, decent at landscapes (with the right technique) and a general-purpose walkaround lens. Since a lot of folks like to do these things, and the manufacturers figure you'd like to use your shiny new camera out of the box, and you can't use a camera body without a lens, this is why it's included in kits.
It's routinely trash-talked on boards because it's so "low quality" but the truth of the matter is it does not automatically turn all your images butt-ugly. And a high-quality lens can't stop you from turning out butt-ugly images if you can't compose or don't know how to use a camera/lens. Yes, there are nicer lenses out there, but technique is more likely to get in your way in the beginning than your lens (see: Why are my photos not crisp?). There are sharper, faster, wider, longer, and bigger-zoom-ranged lenses out there. But they also cost 5-10 times more.
The 18-55 is a good way to help solve that "chicken and the egg" dilemma by giving you experience with a lens, even if it's not an ideal lens. To me, the "body only" option is offered not so beginners can ala carte their lens choices, but so folks who already have their glass and want to upgrade the body don't have to get stuck with another kit lens.
Will these two lenses cover all types of photography, such as fashion blogging and family get [..] together for example?
They may. They may not. The family get together in particular may be tough, because your only low light lens is going to be the 50/1.8. It may be a little long on a crop (DX) body for group shots or across-the-table shots. Fashion blogging, possibly, depending on the blog and the type of shots you're envisioning. Full-length body shots with a 50/1.8 can mean being farther away from your subject than you'd like.
But essentially, even with the 18-55, you've only gotten what I call "the training wheels triple": the three low-cost decent lenses that you're going to want to replace eventually down the road with what you really want.
The 50 is fast, but may not be wide, sharp, or long enough, depending on what you want to do with it (portrait shooting, really, is about lighting, not bokeh). The 70-300 is slow (i.e., has a maximum aperture smaller than f/2.8 (usually f/3.5-5.6)--a smaller maximum aperture means you have to use slower shutter speeds or higher ISO in lower light) and optical image quality @300mm may require a little coaxing and technique, so not great for fast-moving subjects or long enough for small wildlife (like birds). The 18-55 is wide, but not ultrawide, and it also is typically slow.
And none of them are macro lenses. :) Just saying. I did what you did, only I also got the 18-55. (In my day, with the Canon XT, it was the 18-55 II, the 75-300 III, and the EF 50mm f/1.8 II). And I thought I was all set. I now no longer shoot with my XT or any of those lenses. I have a 50D, a 5DMkII, I own three Ls, each of which cost me about $1k, and I also have a full micro four-thirds setup. The path you're embarking on can get very expensive.
But again, I'm an eccentric. And you're not me. :)
See also: Lens upgrade paths (sub $1000) for the EF-S 18-55mm IS kit lens for Canon APS-C cameras [while it seems like a Canon question, you can translate into Nikon terms].