If it was your first ride, it is no surprise that you struggled going up hills. Even very fit people have trouble riding a bicycle uphill no matter how good a bike they have if they are new to the sport. If your bike has 105 components, it is likely that it isn't a 2010 model. The 2010 was equipped with a 9 speed Tiagra drivetrain. Yours is probably an earlier model like the 2009:
https://www.bicyclebluebook.com/valu...product/17314/
The book value of a 12 year old bike is no measure of how good a bike it is. The 2009 Scott Speedster s30 was a $1300 bike when it was new and a very good starting point for starting not only cycling, it could also have been seen as a good entry level race bike. If yours is in good shape, it certainly will not hold you back for several years. One thing I noticed was the 11-25 original equipment cassette. Moving to an 11-28 cassette would provide an easier hill climbing low gear. You would also need a new slightly longer chain to go with it. Another upgrade would be better tires, the original Hutchinson Equinox tires are very basic quality and quite heavy. Upgrading tires, cassette and chain would not be all that expensive and would provide a noticeable improvement