You should be able to force it to shut down or restart, either by pulling the battery out (if the 310 has a removable battery) or by pressing and holding the power button (which may take 15-20 seconds). Then see whether you can get into recovery.
But since the problem apparently happened the moment you installed the recovery I have to ask: was it the right recovery, i.e. was that particular CWM built for the Desire 310? A recovery that was built for a different device could cause a lot of problems. If it was the right recovery, did you check the md5 code before flashing to ensure you had a good download?
If the recovery really is broken your best bet may be to force a restart, get into the bootloader, select fastboot mode and then either flash a different recovery or use a RUU (ROM Update Utility) to refresh the phone completely. You'll need to find an RUU for that model and also for the cid (customer id, i.e. region/carrier), and I'll admit my usual sources didn't have one for that model so some web searching will be required.
If you can't get it into fastboot mode then you are in real trouble, but hopefully it's not that bad.