Congratulations! It certainly is overwhelming, but the best thing you can do is start planning as soon as possible (after the post-engagement giddiness fades a bit, of course). Just start thinking, you don't have to make any definite plans yet.
Also, get help early. The planning process is too much for one person. Enlist FH, a sister, mama, and whoever else you know can be trusted to stick with you until the wedding. You'll be less stressed this way (learned this too late
)
Congrats again, and good luck!