Discouragement

Well, if you keep moving down, that indicates you haven't found your rating yet. So you wouldn't be getting worse, just still overrated. Keep playing until you stabilize. If you are still not at your correct rating, you might drop even while improving, (for example, if you had 800 rating but were a 400 player who improved to 500, you'd still keep dropping from 800 until you reach said 500, etc.) Once you reach your rating, you will be more evenly matched, winning and losing games at a fairly even rate.
That said, as for improving, you should play a slower time control where you have time to think over your moves. So instead of 10-0, perhaps 15-10, or slower. Focus on not giving away pieces for free and on taking your opponent's pieces when they give them away. Look over your games and post some of your close games or losses you are trying to understand so that players can give you more specific advice and point out ideas to use.