Maybe your IP address has been black-listed 'cause one of your comps is infected. Are you late on any of your bi-annual re-installs
More seriously though it may just have been lag between you and the ISP, and somethings that were being loaded just timed out.
You can get a partial check of how well (i.e fast) data is passing between you and a remote server using 'ping xxx.xxx.xxx.xxx' or 'ping ukbouldering.com'
Under *NIX there is the command 'tracepath' that shows you the complete trace of the servers your data is passing through, from example....
fisher neil # ping ukbouldering.com
PING ukbouldering.com (209.135.140.14) 56(84) bytes of data.
64 bytes from vs314.rosehosting.com (209.135.140.14): icmp_seq=1 ttl=47 time=131 ms
64 bytes from vs314.rosehosting.com (209.135.140.14): icmp_seq=2 ttl=47 time=122 ms
64 bytes from vs314.rosehosting.com (209.135.140.14): icmp_seq=3 ttl=47 time=121 ms
64 bytes from vs314.rosehosting.com (209.135.140.14): icmp_seq=4 ttl=47 time=124 ms
♥
--- ukbouldering.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3017ms
rtt min/avg/max/mdev = 121.469/124.875/131.031/3.668 ms
fisher neil # tracepath ukbouldering.com
1: localhost (192.168.1.100) 0.205ms pmtu 1500
1: router (192.168.1.1) 4.822ms
1: router (192.168.1.1) 1.172ms
2: 10.168.104.1 (10.168.104.1) 22.621ms
3: osr01shef-v15.network.virginmedia.net (62.30.252.129) 43.797ms
4: osr01barn-tenge74.network.virginmedia.net (62.30.252.73) 20.739ms asymm 8
5: osr01brad-tenge71.network.virginmedia.net (62.30.252.53) 24.127ms asymm 8
6: man-bb-a-ge-110-0.network.virginmedia.net (195.182.178.121) 19.682ms asymm 7
7: 212.187.136.125 (212.187.136.125) 44.580ms asymm 10
8: ae-4-4.ebr1.London1.Level3.net (4.69.133.102) 42.011ms asymm 10
9: ae-1-100.ebr2.London1.Level3.net (4.69.132.118) 69.576ms asymm 10
10: ae-43-43.ebr1.NewYork1.Level3.net (4.69.137.74) 98.270ms asymm 11
11: ae-71-71.csw2.NewYork1.Level3.net (4.69.134.70) 130.789ms asymm 12
12: ae-72-72.ebr2.NewYork1.Level3.net (4.69.134.85) 110.176ms asymm 13
13: ae-2.ebr1.Chicago1.Level3.net (4.69.132.65) 127.419ms asymm 14
14: ae-1-100.ebr2.Chicago1.Level3.net (4.69.132.42) 131.384ms asymm 15
15: ae-4-4.car2.StLouis1.Level3.net (4.69.132.189) 126.985ms asymm 16
16: ae-11-11.car1.StLouis1.Level3.net (4.69.132.185) 120.811ms asymm 17
17: RIVER-CITY.car1.StLouis1.Level3.net (4.53.160.10) 126.625ms asymm 16
18: static-216.87.62.241.primary.net (216.87.62.241) 126.741ms asymm 16
19: r-1.core04.stl.rosehosting.com (206.196.99.250) 128.554ms asymm 18
20: vs314.rosehosting.com (209.135.140.14) 126.266ms reached
Resume: pmtu 1500 hops 20 back 47
If there's a lagging/slow node then the above hangs and the total time taken is increased. The above shows ping'ing and tracepathing UKB (looks like ukb is currently hosted in St Louis if names are anything to go by, which they not, so its probably not!).
Got to bear in mind that the internet is still essentially a patchwork network of computers really, and whilst things often work very well, its no surprise that they sometimes fail.