You can run a non-denaturing check gel. If you have molecular weight markers that are appropriate for your size product you can run those. If not, you can run one lane of single strand oligo and one lane of your product. If the anneal was successful, you should see the ds band shifted up. You'll have to use UV backshadowing or a stain such as SybrGold to visualize. Ethidium Bromide is not appropriate for single stranded DNA so that single strand DNA band might not show up on the gel.