That should say, "I've been lifting for five years consecutively."
Five years of on-and-off lifting does not equal five years of lifting. With that minimal training experience, you have no business using anabolics. At 22 years of age, you have very little business using anabolics. At 170 pounds even though you've already got two cycles under your belt, your thoughts really should be shifting away from anabolics and toward re-thinking your nutritional strategies and your dedication to physique-building.
But regardless of all that, no, you probably shouldn't use "Testplex 450", for several reasons other your own personal lack of readiness. It has a stupid name which betrays the credibility of the product and its distributor. I've never even heard of this product. There are many reputable sellers in the PH/DS market, but this is not one of them. Four methyls at once is pretty much always a bad idea, but it's especially bad for a novice user and trainer such as yourself.
I'd stop looking at things like "Testplex 450" and start looking at articles on training and nutrition.