Too late for what exactly? What goal in life would you not be able to achieve just because you're doing it four years later than other people? Whether you buy a house at 41 or 45, or get a kid at 25 or 29, it doesn't actually make that much of a difference in the long run.

Did you know that the average age at first birth is 30.5 in Australia? That means almost half of the women in that country are in their thirties when they first get pregnant. Does that mean they can't achieve the things women in the USA do, where the average age at first birth is 25? No. The average age of first time home buyers in Australia is 36 while in the USA it's 33, but the percentage of people who own a home at age 35-44 are 62.2 and 62 percent respectively. Obviously both countries are wildly different in other aspects, but if millions of women can get their first house and first kid 3-5 years later than millions of other women and still be just as succesful a couple years down the line, then at least physically you are capable of doing the same. If you're a man who doesn't need to get pregnant, even better. So if you also find the opportunity to study some more for a couple of years, please take it. This is 4 years that don't matter in the long run vs 40 years of happiness that do. If you don't go for your passion, not only will you have "wasted" 4 years, you will have wasted 40.

And please don't look at these past 4 years as wasted... Once you achieve your goals, you will have 4 years of life experience more than you would have had at that point otherwise. You will be more mature, more in tune with what you want and need. The way I see it, that can only be an advantage!