Name confusion

My name is Nathan, and in Katakana It's ネイサン, is this correct?

If so, if I were to introduce myself as ネイサン, wouldn't it sound like I'm using the "san" title tacked onto "Nei"?

Basically I wouldn't want to confuse anyone by making them think I'm using an honorific title on myself.

Also, if one were to call me "Neisan-san", wouldn't this be a little odd?

Can someone clear up this confusion for me?
Thank you.

Introduce yourself using the English pronunciation first, and then if anyone is having trouble with your name, clarify by using the katakana pronunciation.

That way no-one will think that you are referring to yourself as "san".

It won't sound particularly odd if someone calls you "Neisan- san", as the emphasis on the two "sans" is different.

I hear very few people in Japan call me "first name+san" anyway- my friends just use my name without san, and people I don't know well use my family name plus san.

I work in a non Japanese company, and while all of the Japanese people have familyname-san, ALL of the foreigners are always called by givenname-san.

Yes, that does happen. If Nathan really doesn't want to be called "Neisan-san" though, he should use his family name, or a short version like Nate for example.

However with normal Japanese intonation "Neisan-san" doesn't sound as odd as he thinks it does.

My name is Nathan, and in Katakana It's ネイサン, is this correct?

Yes, that is the typical way to write your name in katakana.

If so, if I were to introduce myself as ネイサン, wouldn't it sound like I'm using the "san" title tacked onto "Nei"?

I don't really think so, and even if it did, what can you do about it? It's your name. But I think it will only remind a lot of Japanese people of the famous actor Ethan Hawke. Or maybe some would mistakenly assume you're saying "older sister (neisan)," but who cares.

Basically I wouldn't want to confuse anyone by making them think I'm using an honorific title on myself.

That's not a big confusion. But you can always introduce yourself by saying, "Neisan (family name) desu." to avoid the confusion if that makes you comfortable.

Also, if one were to call me "Neisan-san", wouldn't this be a little odd?

Not really. Locals normally use a lot of similar terms. Mitsui Bussan-san (famous company name +san), Hosshan-san (famous celebrity Hoshino's nickname +san), and there are Japanese family names like Hisama. A Mr. or Ms. Hisama would be called Hisama-sama at a bank or hotel. But you can always say, "Neisan to yonde kudasai. (Call me Nathan.)" if that makes you comfortable.

Hope all is clear Der Kommissar.