Yes and no.
Yes, because, as Emily Post et al say, you should be gracious when it comes to gifts. While the motivation may have been wrong, wrong, wrong, it was still a gift. It was still a nice thing to do, even if it was a Secretaries' Day obligation, etc.
That having been said, no, you aren't being petty.
This is an issue of perception. There are a few ways to handle it, going from easy to more difficult but probably more permanently successful.
(1) Look for small things that you do which are clerical/secretarial in nature. And, if you can without jeopardizing your job or anyone's safety, stop doing them. E. g. don't accept the FedExes that come in, don't water the plants, don't change the coffee filter, don't do someone else's copying. These things all smell clerical to coworkers. While you may not intend that, e. g. you're being responsible re the FedExes, you don't want the plants to die, you like fresh coffee and you just want to help out, it may not be seen that way. These days, there are varying degrees of clerical, everything from answering phones and light filing to putting together simple (not complex like you do) spreadsheets. So the confusion is understandable. Don't reinforce the perception of you being clerical by doing things that are more clearly secretarial in nature.
(2) Go to www.salary.com and do a little homework. Look up Analyst, Business Analyst, Data Analyst and Database Analyst. I used to do something similar to you (pivot tables, etc.) but I was called a Business Analyst. So that might fit with you as well. Once armed, have a private chat with your boss. Explain what you do. Show how it is related to any of these positions. Suggest a title change for your position. Explain that you are not trying to parlay this into a raise. Rather, it's to make it clear that you are an analyst rather than a clerical person. So you're talking business cards (if applicable) and a desk sign (if applicable). Plus the new title. Nothing more.
(3) If you sit some place that can be conceived as being clerical (that means up front), ask to move. I used to sit in a cube at the front of an aisle and was asked all the time about where meetings were, etc. No one else in my team was asked that. Hence that might work, but keep in mind that your boss might only be able to play around with certain cubes and to move you might mean that s/he has to trade with another manager. Hence it may not be easy, but it's possible. However, just a move might not do the trick. People may still seek you out even if it gets less obvious that you are the go-to person for asking where the big meeting is or how to work the fax machine.
(4) Again, back to www.salary.com. Now, what if you fit into only part of one of the positions I outlined? The answer is to go back to class and get some more education. If you are doing pivot tables in Excel, you will be able to learn MS Access fairly easily. You most likely will be able to go straight to the Intermediate class rather than the Beginner class. Nothing spells analyst more than knowing how to use a database program. So go to class -- and have the company pay for it. If the company doesn't use Access, they must use some other data program (Oracle or MS SQL Server are #1 and #2, respectively. Together they have over 50% of the commercial market), so learn that. Oracle takes longer to learn (I took 3 8-week courses instead of 2 four-hour classes), but it's unmistakeable. Ask the DBA (Database Administrator) what your company uses. After all, you get the data for your spreadsheets from somewhere.
Don't want to learn databases? Don't fret. You're more than halfway there by knowing pivot tables. Just like pivot tables require you to put a label at the top of a column and a label to the left of a row, similar things happen when you query databases. You use tables to get the information you need. Databases are more flexible than pivot tables. A simple database query is essentially a pivot table. If your company doesn't want you to do this, or if they won't pay for it, buy MS Access (a few hundred bucks) and start to teach it to yourself at home. While it may not be needed for this job, it's a good skill to have and is useful for your resume.
(5) Go back to college, and not just for certification in a computer language (SQL would be your best bet) or to learn one program, but to get a computer science degree. Yes, you have 2 college degrees. Hey, I have a college degree and a JD, but I didn't really start to get respect in Engineering Land until I took SQL and Oracle DBA classes at BU. This is harder, it's more expensive (although your company should foot part or all of the bill) and a lot more effort, but they'll never confuse you with a secretary again.