Theland, you are on very early days still. The first 3 weeks I started on antidepressants, I couldn't leave my bed for 3 weeks. Thank god for my sister looking after my children...
You are not going to get a straight upwards improvement, more likely, you will just start to get more good days than bad.... over a few weeks and onwards, and that's the aim.
They don't make you feel "happier", they help the depression to lessen, so you can do more normal things- more like a crutch. But when you consider, you are trying to retrain your mind and body to react differently... it is not going to work fast.
If you have a crisis, you may need a fast-acting, fast wearing off medication... a sedative say (like valium in old language), so you can get more help if you need, but they are short-term, addictive, and don't help the condition in the longrun.
Stay in touch with your GP, but don't be fobbed off either x