is it just me?

yes, it's just you

. . . or am I all on my own again?? para para... you're in taj mahal...

Huh, sorry. I'll have to correct you here...
First. These aren't coins, these are points.
Second. It is literally impossible that you should get less points than any of us.

I hope that answers your question. :)

Viva españa.

Points increase whenever a user makes a public giveaway, and cap to 300 (outside of removal of an active giveaway you are entered in, which can boost it higher for a short while).

So either you are at the cap, or no one is making giveaways right now.

From the Steamgifts FAQ:

"Every time anyone submits a game, every member of the site, excluding the giveaway creator, receives 5 percent of that gifts value (in USD) in points. For example, if a $50 gift is created, every user on the site receives 2.5 points. And, if a $20 gift is created, everyone would receive 1 point."

So perhaps you are the only person creating giveaways right now, and thus everyone but yourself is getting the precious points? Hmm, guess not.

I wouldn't know. My points are always stuck at 300 anyways,

You only get points when giveaways are created, if no one has created a giveaway for a little while, it makes sense for your points to have not increased.

If you require a few more for a giveaway which interests you, you can click "Giveaways" "View Entries" and remove your entry from one of the ones you may have had second thoughts about, or is still weeks away from being complete.
Depending on the value of the game you should/could have enough points to enter another giveaway, and with luck, you'll be able to re-enter the one you left if it still has not finished, and you are still interested in it.

Simple Version: Points come when points want or when people make giveaways.
Detailed Version: FAQ.