Motorcycle won't start?

I have a 2006 Suzuki GS500F. Tried starting it today and I only got a constant clicking noise as long as I held the starter. Eventually I checked the battery (granted I have no clue when it comes to maintenance) but everything was plugged in. Went to start it again and this time I didnt even get the clicking noise. I thought I'd give the horn a try and alls I got was a barely audible beep out of it. Would I be correct in assuming I just need a new battery? Any advice?