Well I would think that the quick "What's for lunch?" may be fear of Dukkha, yes, fear of getting too heavy. Perhaps you don't believe there's a way out of Dukkha enough. Perhaps it could be not enough balance in your Compassion/Lovingkindness wish. Because as I said before, the first two Noble Truths are pretty heavy unless we have the third and the fourth. If we open to death and Dukkha it can be pretty heavy unless we understand that there's a way out of Dukkha. Perhaps strengthening your confidence that there's a way out of Dukkha will give you more courage to open to Dukkha. Sometimes the fear of opening to Dukkha doesn't give you the opportunity to really develop that compassionate motivation that is very powerful in our practice. If you're seeing that there is a fear to open to Dukkha, and a wishing to look for the pleasant, quick, pleasure like "What's for lunch?" sense desire, then perhaps you think that the only way out of Dukkha is worldly happiness.
Ask yourself, "Do I really believe in a way out of Dukkha?" and "What have I seen in myself that has helped me understand that there is a way out of Dukkha?" This will help to bring more balance in the Compassion/Lovingkindness meditation, and a more belief that people have this potential to overcome suffering, not just by distracting themselves into worldly happiness. Because worldly happiness is only temporary, we call it a temporary relief from Dukkha. But it doesn't actually get to the roots of it. I seem to be talking a lot about the third and the fourth Noble Truths today! Strengthening our understanding of the Noble Eightfold Path, and that it's possible to end suffering, may help to bring forth more Lovingkindness to balance the Compassion.
Equanimity also helps in not feeling that you're going to be overwhelmed by the suffering of others when you open to it. We need a balance between Compassion and Equanimity. Perhaps you feel that if you open to others' suffering you're responsible for it. That could be a burden. We're just trying to help with what we can, but it's really not our responsibility to walk the path to the ending of Dukkha for everybody, because it's impossible. So, we open to Dukkha, to understand and motivate us to walk the path out of Dukkha and be of more benefit, so we can perhaps lessen some of the Dukkha in the world. Equanimity comes from reflecting that everybody is the owner of their own Kamma, which is actually the first teaching from a Buddhist teacher that we received. So, we believe that everybody is the owner of their own Kamma. It's our responsibility to take care of our Dukkha and we can't change the Kamma of others.