noun. One who worries excessively and needlessly.

noun. A person who worries excessively, especially about unimportant matters.

noun. thinks about unfortunate things that might happen

"And yesterday, Sunday, I lamented that going to the movies has become much less of a pleasure for me these days and more of an exercise in worrywart-ism."

OCD  hypochondriac  pessimist  

kill-joy  party pooper  spoilsport  wet blanket  

Missie  chappie  creeter  debbil  debil  

bundle of nerves  fussbudget  worrier