I had my nose pierced April 1 and now there is an ugly bump...?

You almost certainly do not have a keloid. Keloids associated with piercings are actually extremely rare, and usually are only observed in African American individuals (no one knows why, but African Americans seem to be more strongly predisposed to keloids).

But that's a common mistake. Most people think that they have a keloid, when they actually have hypertrophic scarring. Hypertrophic scarring is actually very common with cartilage piercings. And, in fact, keloids and hypertrophic scars are almost the same thing. Both are due to a build up of collagen around an injured area. The difference is that the collagen in a keloid is aligned every which way, making reabsorbtion almost impossible (really the only treatment for a keloid is steroid injections, and those don't always work). But in a hypertrophic scar, the collagen is aligned well. This makes reabsorbtion possible.

Actually, hypertrophic scars usually go away with proper care and time. The things you've been doing aren't really helping you though. Sea salt soaks are what you should be doing in the first place, to clean your piercing. The soothing head of a sea salt soak can also help with the hypertrophic scar. This is good, keep them up. But do not do any sort of sea salt paste; it's just way too harsh on your piercing (sea salt concentration should never be higher than 1/4 tsp per 8 fl oz of water for a piercing. Pastes are unacceptable) and can actually make the scar worse, due to irritation. H2Ocean is basically the same thing as a sea salt soak, only used cold, so while it may disinfect the piercing, you don't get the whole benefit of a sea salt soak; half the benefit is in the heat and soaking. Don't use tea tree oil. For some reason a lot of people think that it will help with a hypertrophic scar, but in reality, it's far too harsh to put on a piercing (if I recall correctly this product actually has alcohol in it: very bad). Don't use Hydrocortisone cream either. That won't do anything good for your piercing, and like the sea salt paste and tea tree oil, might actually hurt it.

So what should you do? Well your sea salt soaks are good. Keep them up. Also, do extra hot compresses with plain water. And I've heard people (body mod enthusiasts who know what they're talking about, not just random people) swear by Chamomile tea bag soaks, though I can't personally vouch for that. I do have experience with Emu oil however, and it's a great product. But it can be a bit expensive and hard to find. Also you should keep the oil on the bump only, and do your best to keep it out of the piercing. You'll need to massage it in for a while; it won't work if you just slather it on.

Really, in whatever of the above suggestions you prefer, what you're looking for is the combination of heat and massage. This is the best technique to get the collagen to reabsorb. And like I said, it probably will, if you treat the piercing right and give it time.

I doubt it is a keloid because usually a keloid would be in the exact spot where the piercing is. It's probably just a pimple. Using a facial wash or anything with acne medication in should get rid of it.