Google Nexus 5 — Lost all contacts - help!

Help- Android Users!! I've lost nearly all contacts!! Phone battery died, I charged and turned on and I'm left with 20 contacts! Checked Gmail contacts online and only shows 11 in any folder. Last sync was 5.05pm. No contacts recorded on SIM. Remaining contacts are a mix of manual entry, 'saved from' and Skype for Business/O365 so no logic! Argh!!!! I just assumed everything was backed up automatically these days It's cached somewhere though as a friend who has disappeared from my contacts has just text and it came up with her name!!