7-10 months is their first stage of seperation anxiety, here is an article from Parenting Magazine (a couple of issues ago)
Separation Anxiety Age-by-Age - Parenting.com
As for taking a shower, I know its hard, some days its hard for me to get ready in the morning, my daughter is going through this as well. Remember that this too shall pass. Do your best to make sure he knows you love him and you are there for him, but as parents we have to be good examples and take care of ourselves too.