Hey pal.
Spam links will not harm your site as in you will not lose rankings or trust, you will just not gain any and obviously if you don't gain any rankings or trust then you won't make any progress.
Obviously the big g likes to see obl aswell as ibl (both domain and kw anchor) so keep your comments locked and just do some obl yourself. as a website owner you should always be in controll of your sites content.
Also, don't worry about obl too much, just focus on quality unique content and ibl then you will do fine in the serps.
Hope this helps
BHD x