Keep it up! Starting out your workout journey is always a series of ups and downs and it's easy to feel like you've plateaued. If you're feeling a bit more adventurous, I'd suggest trying the Insanity videos. It's a bit crazy all at once but you could work yourself up to do the first 10 minutes, then slowly the first 15, then first 20. The key is to keep up the intensity and your form more than timing! Keep us posted on how things go!