You'll need to "adjust" your 2017 tax return to report your 2017 expenses. Expenses cannot be carried forward to another year and applied against that year's income. If you had "Capital Costs" (items for which you are claiming Capital Cost Allowance or depreciation on), you could choose to use these in a future year as CCA is an optional claim.
Here's a little more information you might find helpful from TurboTax on CCA and Expenses: https://bit.ly/2NUNalo