You may be overextended today and need to shift the focus onto yourself. It's not the end of the world if you postpone doing someone else a favor, and it doesn't mean you're not a good friend if you don't say 'yes' to every invitation. Build yourself up from the inside. This means spending time on something that nourishes your body. Strength building exercise, such as Bikram yoga, would be especially beneficial to you at this time.