It may not have been the EKG it probably was the X-ray that they also took when they were referring to the enlargement. I appreciate the advice and will do my best to seek medical attention.
I forgot to mention in my first response, the BP is marginally high, but that too is not necessarily a problem, as BP is very emotion related. Try to take your BP several time when you are in Walmart or any store that has a pharmacy (i.e., a self-operated BP station) and see what you BP tends to be most of the time. If it remains high, that too suggests the need for medical attention/treatment/medication. Also, a rest HR over 100 isn't a big threat either, but it is a bit too high in my view, potentially a problem indicator.
The 2007 pass on the EKG is a good sign, but I don't understand that as it relates to the heart size/enlargement. If that can be "seen" on an EKG it is news to me, may be, but news to me.
Still, you have your young age going for you, try a health life style (including no caffeine) and see if that reduces symptoms, improves HR/BP numbers. Did I already say? you may benefit from a aspirin a day, take with a meal.
I forgot to mention that earlier, during my annual check ups I had an EKG every year and I had one back in 2007, and they said that there were no abnormalities or any signs that the heart had enlarged.
It sounds like you need a good general physical check-up with an EKG. At your age the EKG many not normally be done, but you do have heart symptoms that should have at least that check.
Many people have a heart murmur and live a long life without having to take any action, so it may be unrelated to your problem.
Talk with a clinic or other lower-cost medical facility to find out what they charge for a physical, I think it should possible to get that done for a few hundred $$, no more that a good set of tires for a car, figure out some why to pay for it, it should be done.