keep goin this way, Amy!
I know how hard is to start exercising instead of sitting on the couch
But now just have in mind that 1st week is the hardest! Then it will become like natural thing, the part of the day and so on.
But don't push yourself too hard, because u will get tired from this and couch wins.. Begin with small steps, so with half an hour, and after week you can add 10 more minutes, and keep adding them when you feel it's already too less to get wet

First weeks is not about reaching 45 min or else, it's about making exercising a habit
Good luck, You can do it!