Lots of good thoughts from good riders above. I'll mention 3 more things:

1) At a minimum, use the 20/20 principle. Every 20 minutes, get out of your saddle and pedal 20 strong strokes while standing. That gets the blood flowing to all the parts, and relieves pressure. Doing that every 10 minutes is even better, especially as you adapt to longer rides.

2) The symptoms you describe can happen even if you are using the perfect saddle. It's just not natural for the human body to sit on a saddle for hours at a time. Barring a true misfit, the good news is that you and your body will adapt over time. As a personal example, I can ride 100 miles mid-season with no pain at all. Early in the spring, it may get tender after 30 miles. After being off the bike for 5 months, I start to feel it after even 10 miles. All of those experiences are on the exact same type of saddle that I've been riding 4-5,000 miles per year since I switched to it in 2004.

So don't expect that you shouldn't experience any discomfort as you increase your mileage. I'd definitely consider all of the other good advice above, but just don't feel like you immediately need to go out to buy a new saddle either. I'd check the saddle fit, but then give it a little more time (and miles) before switching to something new.

3) Check your tire pressure vs your weight. The recommended tire pressure on the sidewall can be way too much for your weight, making for a harsher ride. Do a Google search to determine the right pressure, and don't be satisfied until you find one that recommendss different pressure for front and rear. The front requires less pressure because there is less weight on the front tire. On smooth roads you may not notice a difference, but I guarantee that you will when the pavement gets rougher.
Good luck.