On mental health?

I’ve received an email a few days ago to review a paper:

[…] We have received the following manuscript to be considered for publication in Mathematics (http://www.mdpi.com/journal/mathematics/) and kindly invite you to provide a review to evaluate its suitability for publication. […] If you accept this invitation we would appreciate receiving your comments within two weeks [stress is by me]. Please let us know if you will need more time. […] Since I didn’t know the journal, didn’t have access to the paper till I accepted the review, and didn’t think that I could do the work in two weeks, I rejected the invitation, and they had asked if I am rejecting the invitation to recommend someone else to review the paper. 2 weeks is not enough time for me to review a paper, and I am not aware of anyone who I know that would do this in two weeks to recommend. Their response: […] If you have declined review invitation just because of matter of time, we would like to grant you an extension. If you are still interested in reviewing this manuscript, please let me know. […] And mine: […] Thanks for the extension. There are a couple of things that I need to mention. I do not feel that being under the impression that I am granted an “extension” for a job that I haven’t agreed on its original due date would be very healthy for me. Moreover, I tend to not to do service work for journals that charge authors. […]