Lump/Wart that is on St. Bernard's face, Help?

Recently we noticed what we thought was another wart (he has a couple black warts on his face) on my St. Bernard (who will be 6 in September). It has since begun to drain what we think is pus, the site smells and his hair was getting stuck in the drainage. He has no pain or irritation when you touch it. It looks like a wart or almost like a nipple that is red and draining pus. I cleaned it with hydrogen peroxide to try to take the smell away and get it cleaned but the pus keeps coming out. It has what looks like a little hole in the middle (not very deep, like an indent) so i suspected a tick that embeded under the skin, we tried squeezing it but nothing is coming out. He scratched his face with his back leg after i cleaned it and caught it with his nail, it started to bleed a little but did not bother him, he let me clean it again. I have been reading up on it and it seems like wart and lumps like this are normal for older dogs, but this is infected and i am worried that it could be a tick which caused an infection. If anybody has any past experience with anything like this or knows what i could be dealing with please let me know asap. Thank you