How many colleges to apply to?

I only have two colleges currently that I am applying to. Clemson University in South Carolina is my number one choice. If I get in I’m going there no matter what. My other choice is The Ohio State University. Honestly the only reason why I’m applying is because it is the only one of the few schools in Ohio (the state I live in) that offer architecture as a major that I would want to attend. Do I need to apply to more colleges?
Here are my stats-
Class rank: 1 of 70
GPA: 4.4 weighted
ACT(taken once): 33 composite, 34 on math, 34 on science, 33 on english, 32 on reading, and 10/12 on writing
Community Service: 100+ hours
E.C.'s: Class Secretary, STUCO, JV/Varsity Basketball(9-12), JV/Varsity Volleyball(9-10), Marching Band/Drum Line(6-12), Choir/Scarlet Angels(all girls singing group)/XVI(a cappella group I founded)
AP classes: took 3 junior year and passed all of the tests, taking 4 this year

Should I apply to more than 2 colleges or do I have good enough chances of getting into both I’m currently applying to? Thanks!

Yes you do. Your record is admirable and you should get into Clemson. But then, there’s the issue of cost. How much an your parents afford? Have they given you an amount?Have you run the NPC together for both Clemson and tOSU?
You want to give yourself a real choice for next Spring. Do you really want your only choice to be tOSU if Clemson, for any reason, doesn’t pan out?
If you like the South, UAlabama Tuscaloosa would be an obvious choice: with your GPA and test scores, you automatically qualify for Honors College, Honors Housing, a stipend and a full tuition scholarship. It’s similar enough to Clemson to be a good financial and academic safety, and architectural engineers have excellent job prospects, unlike “straight” architecture majors.
http://cce.eng.ua.edu/undergraduate/architectural-engineering/
Straight architecture is available at Auburn, which is also similar enough to Clemson and has some scholarships.
http://cadc.auburn.edu/architecture